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Yu H, Wang X, Tian R, Li X, Xu C, Fei J, Li T, Yin Z. Myometrium infection decreases TREK1 through NHE1 and increases contraction in pregnant mice. Am J Physiol Cell Physiol 2024; 326:C1106-C1119. [PMID: 38344766 DOI: 10.1152/ajpcell.00598.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 02/07/2024] [Accepted: 02/08/2024] [Indexed: 03/23/2024]
Abstract
Intrauterine infection during pregnancy can enhance uterine contractions. A two-pore K+ channel TREK1 is crucial for maintaining uterine quiescence and reducing contractility, with its properties regulated by pH changes in cell microenvironment. Meanwhile, the sodium hydrogen exchanger 1 (NHE1) plays a pivotal role in modulating cellular pH homeostasis, and its activation increases smooth muscle tension. By establishing an infected mouse model of Escherichia coli (E. coli) and lipopolysaccharide (LPS), we used Western blotting, real-time quantitative polymerase chain reaction, and immunofluorescence to detect changes of TREK1 and NHE1 expression in the myometrium, and isometric recording measured the uterus contraction. The NHE1 inhibitor cariporide was used to explore the effect of NHE1 on TREK1. Finally, cell contraction assay and siRNA transfection were performed to clarify the relationship between NHE1 and TREK1 in vitro. We found that the uterine contraction was notably enhanced in infected mice with E. coli and LPS administration. Meanwhile, TREK1 expression was reduced, whereas NHE1 expression was upregulated in infected mice. Cariporide alleviated the increased uterine contraction and promoted myometrium TREK1 expression in LPS-injected mice. Furthermore, suppression of NHE1 with siRNA transfection inhibited the contractility of uterine smooth muscle cells and activated the TREK1. Altogether, our findings indicate that infection increases the uterine contraction by downregulating myometrium TREK1 in mice, and the inhibition of TREK1 is attributed to the activation of NHE1.NEW & NOTEWORTHY Present work found that infection during pregnancy will increase myometrium contraction. Infection downregulated NHE1 and followed TREK1 expression and activation decrease in myometrium, resulting in increased myometrium contraction.
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Affiliation(s)
- Huihui Yu
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xingxing Wang
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Ruixian Tian
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xuan Li
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Chenyi Xu
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jiajia Fei
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China
| | - Tengteng Li
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zongzhi Yin
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, China
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Malvasi A, Ballini A, Tinelli A, Fioretti B, Vimercati A, Gliozheni E, Baldini GM, Cascardi E, Dellino M, Bonetti M, Cicinelli E, Vitagliano A, Damiani GR. Oxytocin augmentation and neurotransmitters in prolonged delivery: An experimental appraisal. Eur J Obstet Gynecol Reprod Biol X 2024; 21:100273. [PMID: 38274243 PMCID: PMC10809121 DOI: 10.1016/j.eurox.2023.100273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Accepted: 12/22/2023] [Indexed: 01/27/2024] Open
Abstract
The uterus is a highly innervated organ, and during labor, this innervation is at its highest level. Oxytocinergic fibers play an important role in labor and delivery and, in particular, the Lower Uterine Segment, cervix, and fundus are all controlled by motor neurofibers. Oxytocin is a neurohormone that acts on receptors located on the membrane of the smooth cells of the myometrium. During the stages of labor and delivery, its binding causes myofibers to contract, which enables the fundus of the uterus to act as a mediator. The aim of this study was to investigate the presence of oxytocinergic fibers in prolonged and non-prolonged dystocic delivery in a cohort of 90 patients, evaluated during the first and second stages of labor. Myometrial tissue samples were collected and evaluated by electron microscopy, in order to quantify differences in neurofibers concentrations between the investigated and control cohorts of patients. The authors of this experiment showed that the concentration of oxytocinergic fibers differs between non-prolonged and prolonged dystocic delivery. In particular, in prolonged dystocic delivery, compared to non-prolonged dystocic delivery, there is a lower amount of oxytocin fiber. The increase in oxytocin appeared to be ineffective in patients who experienced prolonged dystocic delivery, since the dystocic labor ended as a result of the altered presence of oxytocinergic fibers detected in this group of patients.
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Affiliation(s)
- Antonio Malvasi
- Department of Biomedical Sciences and Human Oncology, University of Bari, 70121 Bari, Italy
- Unit of Obstetrics and Gynecology, University of Bari, Bari, Italy
| | - Andrea Ballini
- Department of clinical and experimental medicine, University of Foggia, Foggia, 71122, Italy
| | - Andrea Tinelli
- Department of Obstetrics and Gynecology and CERICSAL (CEntro di RIcerca Clinico SALentino), Veris Delli Ponti Hospital, 73020 Scorrano, Italy
| | - Bernard Fioretti
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via dell'Elce di Sotto 8, 06132 Perugia, Italy
| | - Antonella Vimercati
- Department of Biomedical Sciences and Human Oncology, University of Bari, 70121 Bari, Italy
- Unit of Obstetrics and Gynecology, University of Bari, Bari, Italy
| | - Elko Gliozheni
- Section of Obstetrics and Gynecology, Department of Medicine and Surgery, University of Perugia, 06156 Perugia, Italy
- University of Medicine of Tirana, Department of Obstetrics and Gynecology, Tirana, Albania
| | - Giorgio Maria Baldini
- Momo Fertilife, IVF Clinic, Bisceglie, 76011, Italy
- University of Bari Aldo Moro, 70121, Bari, Italy
| | - Eliano Cascardi
- Department of Precision and Regenerative Medicine and Ionian Area, University of Bari “Aldo Moro”, Policlinico of Bari, Piazza Giulio Cesare 11, 70124 Bari, Italy
| | - Miriam Dellino
- Department of Biomedical Sciences and Human Oncology, University of Bari, 70121 Bari, Italy
- Unit of Obstetrics and Gynecology, University of Bari, Bari, Italy
| | - Monica Bonetti
- Department of Biomedical Sciences and Human Oncology, University of Bari, 70121 Bari, Italy
- Unit of Obstetrics and Gynecology, University of Bari, Bari, Italy
| | - Ettore Cicinelli
- Department of Biomedical Sciences and Human Oncology, University of Bari, 70121 Bari, Italy
- Unit of Obstetrics and Gynecology, University of Bari, Bari, Italy
| | - Amerigo Vitagliano
- Department of Biomedical Sciences and Human Oncology, University of Bari, 70121 Bari, Italy
- Unit of Obstetrics and Gynecology, University of Bari, Bari, Italy
| | - Gianluca Raffaello Damiani
- Department of Biomedical Sciences and Human Oncology, University of Bari, 70121 Bari, Italy
- Unit of Obstetrics and Gynecology, University of Bari, Bari, Italy
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Shynlova O, Nadeem L, Lye S. Progesterone control of myometrial contractility. J Steroid Biochem Mol Biol 2023; 234:106397. [PMID: 37683774 DOI: 10.1016/j.jsbmb.2023.106397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/01/2023] [Accepted: 09/04/2023] [Indexed: 09/10/2023]
Abstract
During pregnancy, the primary function of the uterus is to be quiescent and not contract, which allows the growing fetus to develop and mature. A uterine muscle layer, myometrium, is composed of smooth muscle cells (SMCs). Before the onset of labor contractions, the uterine SMCs experience a complex biochemical and molecular transformation involving the expression of contraction-associated proteins. Labor is initiated when genes in SMCs are activated in response to a combination of hormonal, inflammatory and mechanical signals. In this review, we provide an overview of molecular mechanisms regulating the process of parturition in humans, focusing on the hormonal control of the myometrium, particularly the steroid hormone progesterone. The primary reason for discussing the regulation of myometrial contractility by progesterone is the importance of the clinical problem of preterm birth. It is thought that the hormonal mechanisms regulating premature uterine contractions represent an untimely triggering of the normal events occurring during term parturition. Yet, our knowledge of the complex and redundant hormonal pathways controlling uterine contractile activity leading to delivery of the neonate remains incomplete. Finally, we introduce recent animal studies using a novel class of drugs, Selective Progesterone Receptor Modulators, targeting progesterone signaling to prevent premature myometrial contractions.
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Affiliation(s)
- Oksana Shynlova
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, Toronto M5G 1X5, Canada; Department of Physiology, University of Toronto, M5S 1A1, Canada; Department of Obstetrics & Gynecology, University of Toronto, M5S 1A1, Canada.
| | - Lubna Nadeem
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, Toronto M5G 1X5, Canada
| | - Stephen Lye
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, Toronto M5G 1X5, Canada; Department of Physiology, University of Toronto, M5S 1A1, Canada; Department of Obstetrics & Gynecology, University of Toronto, M5S 1A1, Canada
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Porta M, Boening A, Tiemann J, Zack A, Patel A, Sondgeroth K. The Contractile Response to Oxytocin in Non-pregnant Rat Uteri Is Modified After the First Pregnancy. Reprod Sci 2023; 30:2152-2165. [PMID: 36696040 PMCID: PMC10310576 DOI: 10.1007/s43032-023-01163-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 12/24/2022] [Indexed: 01/26/2023]
Abstract
During pregnancy, the uterus undergoes several modifications under the influence of hormonal and mechanical stimuli. We hypothesize that while most of these modifications are reverted during involution, some of the physiological properties of the uterus are permanently altered. To investigate this hypothesis, we conducted motility experiments to evaluate the contractility response of uterine tissue samples from non-pregnant virgin and proven breeder female rats to oxytocin (10-10 to 10-5 M). We found that the virgin tissue contracts more robustly than proven breeder tissue in the absence of oxytocin, yet with oxytocin, proven breeder samples displayed a significantly higher increase in activity. These results could depend on a more elevated expression of oxytocin receptor and/or on an alteration in the intracellular pathways affected by the activation of the oxytocin receptors. Here, we explored the impact of some structures involved in the management of intracellular calcium on the dose response to oxytocin recorded from virgin and proven breeder uterine strips. Specifically, we replicated the dose response experiments in low extracellular calcium (10 μM), in the presence of the intracellular calcium channel blocker ruthenium red (10 μM), and in the presence of the sarcoplasmic-endoplasmic reticulum calcium ATP-ase pump inhibitor, cyclopiazonic acid (10 μM). The results of these experiments suggest that also the expression of proteins that control intracellular calcium availability is affected by the experience of pregnancy. Molecular biology experiments will give us more detail on the magnitude of these expression changes.
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Affiliation(s)
- Maura Porta
- Department of Physiology, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515 USA
| | - Amber Boening
- Master of Biomedical Sciences Program, Midwestern University, Downers Grove, IL 60515 USA
| | - Jonathan Tiemann
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515 USA
| | - Adam Zack
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515 USA
| | - Arjun Patel
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515 USA
| | - Korie Sondgeroth
- Department of Physiology, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515 USA
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Szymanska M, Blitek A. Impaired luteal progesterone synthesis observed in gilts with PMSG/hCG-induced estrus affects the expression of steroid, prostaglandin, and cytokine receptors in the endometrium and myometrium during the peri-implantation period. Annals of Animal Science 2023; 0. [DOI: 10.2478/aoas-2022-0076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Abstract
The present study aimed to examine the effect of impaired progesterone (P4) synthesis, observed in gilts with gonadotropin-induced estrus, on the uterine expression of receptors important for pregnancy establishment. Twenty prepubertal gilts received 750 IU PMSG and 500 IU hCG 72 h later, while 18 prepubertal gilts in the control group were observed daily for estrus behavior. Gilts were inseminated in their first estrus and slaughtered on days 10, 12, and 15 of pregnancy to collect endometrial and myometrial tissues for mRNA analysis using real-time PCR. As we previously described, gilts with PMSG/hCG-induced estrus showed decreased luteal P4 synthesis on days 10 and 12 of pregnancy. PMSG/hCG treatment did not affect P4 receptor mRNA expression in either uterine tissue. In the endometrium, a greater mRNA transcript abundance of estrogen receptors (ESR1 and ESR2), androgen receptor (AR), prostaglandin (PG) E2 receptors (PTGER2 and PTGER4), PGF2α receptor (PTGFR), interleukin 6 receptor (IL6R), and tumor necrosis factor α receptors (TNFRSF1A and TNFRSF1B) was detected in gilts with natural than with PMSG/hCG-induced estrus (P<0.05). In the myometrium, the mRNA expression of AR, PTGER2, and PTGFR was lower, while PGI2 receptor (PTGIR) transcript abundance was elevated in the gilts treated with PMSG/hCG as compared with the control animals (P<0.05). In summary, a decreased luteal P4 level during the peri-implantation period in gonadotropin-stimulated pigs affects endometrial and myometrial receptor expression, with the endometrium being more sensitive to impaired P4 synthesis. Whether the observed changes alter uterine receptivity to local and systemic factors remains to be elucidated.
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Abstract
While there is not a wide range of pregnancy-specific drugs, there are some very specific high-risk areas of obstetric care for which unique pharmacological approaches have been established. In preterm birth, labor induction and augmentation, and the management of postpartum hemorrhage, these pharmacological approaches have become the bedrock in managing some of the most common and problematic areas of antenatal and intrapartum care. In this review, we summarize the existing established and emerging evidence that supports and broadens these pharmacological approaches to obstetric management and its impact on clinical practice. It is clear that existing therapeutics are limited. They have largely been developed from our knowledge of the physiology of the myometrium and act on hormonal receptors and their signaling pathways or on ion channels influencing excitability. Newer drugs in development are mostly refinements of these two approaches, but novel agents from plants and improved formulations are also discussed.
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Affiliation(s)
- Susan Wray
- Women's & Children's Health, Faculty of Health & Life Sciences, University of Liverpool, Liverpool, United Kingdom;
| | - Sarah Arrowsmith
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
| | - Andrew Sharp
- Women's & Children's Health, Faculty of Health & Life Sciences, University of Liverpool, Liverpool, United Kingdom;
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Wang Y, Li X, Wei N, Liu Y, Liu X, Sun R, Huang C, Yao B, Wang H. Automated measurement of endometrial peristalsis in cine transvaginal ultrasound images. Front Physiol 2022; 13:983177. [PMID: 36187777 PMCID: PMC9523211 DOI: 10.3389/fphys.2022.983177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 09/02/2022] [Indexed: 11/13/2022] Open
Abstract
Objectives: Endometrial peristalsis (EP) in non-pregnant uterine can be assessed by visual assessment of transvaginal ultrasound (TVUS). However, visual assessment is subjective, and the outcome depends on the sonographers and video analysts. This study aimed to create a newly developed automatic analysis algorithm for measuring the EP compared to visual assessment.Methods: A retrospective analysis was performed using the datasets from in vitro fertilization and embryo transfer (IVF-ET), who underwent the evaluation of EP by TVUS within 5 days prior to transplantation. 158 cine TVUS images were used to develop the automated analysis algorithm, and 37 cine TVUS images were evaluated by both visual and automated analysis algorithms. The algorithm was developed by applying the optical flow technology and enabled objective analysis of the number, direction, and intensity of EP.Results: The number of peristaltic waves counted by visual assessment was 4.2 ± 2.3 (mean ± standard deviation) and 4.1 ± 2.1 for doctors one and two, respectively. The number of waves counted with the algorithm was 3.6 ± 2.1 at first evaluation and 3.7 ± 2.0 at repeated evaluation. A significant difference was found between the algorithm count and visual assessment (p = 0.001, 0.002, 0.003, 0.008). The ICC values for algorithm versus manuals ranged from 0.84 to 0.96 and 0.87 to 0.96. The numbers of the cervix-to-fundus (CF), fundus-to-cervix (FC), and both cervix-to-fundal and fundus-to-cervix (CF + FC) directions of EP counted by the algorithm were 50, 52, and 32, respectively. The numbers counted by visual assessment were 43, 45, and 46, respectively. The number of EP was the same in 87% of the two algorithm counts. The number was lower between the algorithm and visual analysis (79% with complete agreement). The EP intensity assessed by the algorithm was 2.6 ± 1.1, and the peristalsis velocity was 0.147 (0.07) mm/s.Conclusion: The fully automated analysis algorithm can be used to quantify uterine peristalsis comparable to visual assessment.
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Affiliation(s)
- Yue Wang
- Department of Ultrasound, Peking University Shenzhen Hospital, Shenzhen, China
| | - Xiaokun Li
- Department of Ultrasound, Peking University Shenzhen Hospital, Shenzhen, China
| | - Niya Wei
- Department of Ultrasound, Peking University Shenzhen Hospital, Shenzhen, China
| | - Yuanxi Liu
- Shenzhen Wisonic Medical Technology Co., Ltd., Shenzhen, China
| | - Xinting Liu
- Department of Ultrasound, Peking University Shenzhen Hospital, Shenzhen, China
| | - Ruijie Sun
- Department of Ultrasound, Peking University Shenzhen Hospital, Shenzhen, China
| | - Chan Huang
- Shenzhen Wisonic Medical Technology Co., Ltd., Shenzhen, China
| | - Bin Yao
- Shenzhen Wisonic Medical Technology Co., Ltd., Shenzhen, China
| | - Huifang Wang
- Department of Ultrasound, Peking University Shenzhen Hospital, Shenzhen, China
- *Correspondence: Huifang Wang,
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Wray S, Prendergast C, Arrowsmith S. Calcium-Activated Chloride Channels in Myometrial and Vascular Smooth Muscle. Front Physiol 2021; 12:751008. [PMID: 34867456 PMCID: PMC8637852 DOI: 10.3389/fphys.2021.751008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 09/24/2021] [Indexed: 11/24/2022] Open
Abstract
In smooth muscle tissues, calcium-activated chloride channels (CaCC) provide the major anionic channel. Opening of these channels leads to chloride efflux and depolarization of the myocyte membrane. In this way, activation of the channels by a rise of intracellular [Ca2+], from a variety of sources, produces increased excitability and can initiate action potentials and contraction or increased tone. We now have a good mechanistic understanding of how the channels are activated and regulated, due to identification of TMEM16A (ANO1) as the molecular entity of the channel, but key questions remain. In reviewing these channels and comparing two distinct smooth muscles, myometrial and vascular, we expose the differences that occur in their activation mechanisms, properties, and control. We find that the myometrium only expresses “classical,” Ca2+-activated, and voltage sensitive channels, whereas both tonic and phasic blood vessels express classical, and non-classical, cGMP-regulated CaCC, which are voltage insensitive. This translates to more complex activation and regulation in vascular smooth muscles, irrespective of whether they are tonic or phasic. We therefore tentatively conclude that although these channels are expressed and functionally important in all smooth muscles, they are probably not part of the mechanisms governing phasic activity. Recent knockdown studies have produced unexpected functional results, e.g. no effects on labour and delivery, and tone increasing in some but decreasing in other vascular beds, strongly suggesting that there is still much to be explored concerning CaCC in smooth muscle.
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Affiliation(s)
- Susan Wray
- Department of Women and Children's Health, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Clodagh Prendergast
- Department of Women and Children's Health, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Sarah Arrowsmith
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
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Maxey AP, McCain ML. Tools, techniques, and future opportunities for characterizing the mechanobiology of uterine myometrium. Exp Biol Med (Maywood) 2021; 246:1025-1035. [PMID: 33554648 DOI: 10.1177/1535370221989259] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The myometrium is the smooth muscle layer of the uterus that generates the contractions that drive processes such as menstruation and childbirth. Aberrant contractions of the myometrium can result in preterm birth, insufficient progression of labor, or other difficulties that can lead to maternal or fetal complications or even death. To investigate the underlying mechanisms of these conditions, the most common model systems have conventionally been animal models and human tissue strips, which have limitations mostly related to relevance and scalability, respectively. Myometrial smooth muscle cells have also been isolated from patient biopsies and cultured in vitro as a more controlled experimental system. However, in vitro approaches have focused primarily on measuring the effects of biochemical stimuli and neglected biomechanical stimuli, despite the extensive evidence indicating that remodeling of tissue rigidity or excessive strain is associated with uterine disorders. In this review, we first describe the existing approaches for modeling human myometrium with animal models and human tissue strips and compare their advantages and disadvantages. Next, we introduce existing in vitro techniques and assays for assessing contractility and summarize their applications in elucidating the role of biochemical or biomechanical stimuli on human myometrium. Finally, we conclude by proposing the translation of "organ on chip" approaches to myometrial smooth muscle cells as new paradigms for establishing their fundamental mechanobiology and to serve as next-generation platforms for drug development.
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Affiliation(s)
- Antonina P Maxey
- Laboratory for Living Systems Engineering, Department of Biomedical Engineering, USC Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089, USA
| | - Megan L McCain
- Laboratory for Living Systems Engineering, Department of Biomedical Engineering, USC Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089, USA.,Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA 90033, USA
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Garfield RE, Murphy L, Gray K, Towe B. Review and Study of Uterine Bioelectrical Waveforms and Vector Analysis to Identify Electrical and Mechanosensitive Transduction Control Mechanisms During Labor in Pregnant Patients. Reprod Sci 2020; 28:838-856. [PMID: 33090378 DOI: 10.1007/s43032-020-00358-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 10/11/2020] [Indexed: 12/15/2022]
Abstract
The bioelectrical signals that produce uterine contractions during parturition are not completely understood. The objectives are as follows: (1) to review the literature and information concerning uterine biopotential waveforms generated by the uterus, known to produce contractions, and evaluate mechanotransduction in pregnant patients using electromyographic (EMG) recording methods and (2) to study a new approach, uterine vector analysis, commonly used for the heart: vectorcardiography analysis. The patients used in this study were as follows: (1) patients at term not in labor (n = 3); (2) patients during the 1st stage of labor at cervical dilations from 2 to 10 cm (n = 30); and (3) patients in the 2nd stage of labor and during delivery (n = 3). We used DC-coupled electrodes and PowerLab hardware (model no. PL2604, ADInstruments, Castle Hill, Australia), with software (LabChart, ADInstruments) for storage and analysis of biopotentials. Uterine and abdominal EMG recordings were made from the surface of each patient using 3 electrode pairs with 1 pair (+ and -, with a 31-cm spacing distance) placed in the right/left position (X position) and with 1 pair placed in an up/down position (Y position, also 31 cm apart) and with the third pair at the front/back (Z position). Using signals from the three X, Y, and Z electrodes, slow (0.03 to 0.1 Hz, high amplitude) and fast wave (0.3 to 1 Hz, low amplitude) biopotentials were recorded. The amplitudes of the slow waves and fast waves were significantly higher during the 2nd stage of labor compared to the 1st stage (respectively, p = 9.54 × e-3 and p = 3.94 × e-7). When 2 channels were used, for example, the X vs. Y, for 2-D vector analysis or 3 channels, X vs. Y vs. Z, for 3-D analysis, are plotted against each other on their axes, this produces a vector electromyometriogram (EMMG) that shows no directionality for fast waves and a downward direction for slow waves. Similarly, during the 2nd stage of labor during abdominal contractions ("pushing"), the slow and fast waves were enlarged. Manual applied pressure was used to evoke bioelectrical activity to examine the mechanosensitivity of the uterus. Conclusions: (1) Phasic contractility of the uterus is a product of slow waves and groups of fast waves (bursts of spikes) to produce myometrial contractile responses. (2) 2-D and 3-D uterine vector analyses (uterine vector electromyometriogram) demonstrate no directionality of small fast waves while the larger slow waves represent the downward direction of biopotentials towards the cervical opening. (3) Myometrial cell action event excitability and subsequent contractility likely amplify slow wave activity input and uterine muscle contractility via mechanotransduction systems. (4) Models illustrate the possible relationships of slow to fast waves and the association of a mechanotransduction system and pacemaker activity as observed for slow waves and pacemakers in gastrointestinal muscle. (5) The interaction of these systems is thought to regulate uterine contractility. (6) This study suggests a potential indicator of delivery time. Such vector approaches might help us predict the progress of gestation and better estimate the timing of delivery, gestational pathologies reflected in bioelectric events, and perhaps the potential for premature delivery drug and mechanical interventions.
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Affiliation(s)
- R E Garfield
- Department of Obstetrics and Gynecology, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.
| | - Lauren Murphy
- Department of Obstetrics and Gynecology, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA
| | - Kendra Gray
- Department of Obstetrics and Gynecology, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA
| | - Bruce Towe
- Department of Biomedical Engineering, Arizona State University, Tempe, AZ, USA
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11
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Goldsztejn U, Nehorai A. A myofibre model for the study of uterine excitation-contraction dynamics. Sci Rep 2020; 10:16221. [PMID: 33004882 DOI: 10.1038/s41598-020-72562-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 08/31/2020] [Indexed: 01/12/2023] Open
Abstract
As the uterus remodels in preparation for delivery, the excitability and contractility of the uterine smooth muscle layer, the myometrium, increase drastically. But when remodelling proceeds abnormally it can contribute to preterm birth, slow progress of labour, and failure to initiate labour. Remodelling increases intercellular coupling and cellular excitability, which are the main targets of pharmaceutical treatments for uterine contraction disorders. However, the way in which electrical propagation and force development depend on intercellular coupling and cellular excitability is not fully understood. Using a computational myofibre model we study the dependency of electrical propagation and force development on intercellular coupling and cellular excitability. This model reveals that intercellular coupling determines the conduction velocity. Moreover, our model shows that intercellular coupling alone does not regulate force development. Further, cellular excitability controls whether conduction across the cells is blocked. Lastly, our model describes how cellular excitability regulates force development. Our results bridge cellular factors, targeted by drugs to regulate uterine contractions, and tissue level electromechanical properties, which are responsible for delivery. They are a step forward towards understanding uterine excitation-contraction dynamics and developing safer and more efficient pharmaceutical treatments for uterine contraction disorders.
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Qu M, Lu P, Bellve K, Fogarty K, Lifshitz L, Shi F, Zhuge R. Smooth muscle cell-specific TMEM16A deletion does not alter Ca2+ signaling, uterine contraction, gestation length, or litter size in mice†. Biol Reprod 2020; 101:318-327. [PMID: 31175367 DOI: 10.1093/biolre/ioz096] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/15/2019] [Accepted: 06/04/2019] [Indexed: 12/11/2022] Open
Abstract
Ion channels in myometrial cells play critical roles in spontaneous and agonist-induced uterine contraction during the menstrual cycle, pregnancy maintenance, and parturition; thus, identifying the genes of ion channels in these cells and determining their roles are essential to understanding the biology of reproduction. Previous studies with in vitro functional and pharmacological approaches have produced controversial results regarding the presence and role of TMEM16A Ca2+-activated Cl- channels in myometrial cells. To unambiguously determine the function of this channel in these cells, we employed a genetic approach by using smooth muscle cell-specific TMEM16A deletion (i.e. TMEM16ASMKO) mice. We found that myometrial cells from TMEM16ASMKO mice generated the same pattern and magnitude in Ca2+ signals upon stimulation with KCl, oxytocin, and PGF2α compared to the isogenic control myometrial cells. At the uterine tissue level, TMEM16A deletion also did not cause detectable changes in either spontaneous or agonist (i.e. KCl, oxytocin, and PGF2α)-induced contractions. Moreover, in vivo the TMEM16ASMKO mice gave birth at full term with the same litter size as genetically identical control mice. Finally, TMEM16A immunostaining in both control and TMEM16ASMKO mice revealed that this protein was highly expressed in the endometrial stroma, but did not co-localize with a smooth muscle specific marker MYH11. Collectively, these results unequivocally demonstrate that TMEM16A does not serve as a pacemaking channel for spontaneous uterine contraction, neither does it function as a depolarizing channel for agonist-evoked uterine contraction. Yet these two functions could underlie the normal gestation length and litter size in the TMEM16ASMKO mice.
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Affiliation(s)
- Mingzi Qu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
- Department of Microbiology & Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ping Lu
- Department of Microbiology & Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Karl Bellve
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Kevin Fogarty
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Lawrence Lifshitz
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Fangxiong Shi
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Ronghua Zhuge
- Department of Microbiology & Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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Osaghae BE, Arrowsmith S, Wray S. Gestational and Hormonal Effects on Magnesium Sulfate's Ability to Inhibit Mouse Uterine Contractility. Reprod Sci 2020; 27:1570-1579. [PMID: 32430707 DOI: 10.1007/s43032-020-00185-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Magnesium sulfate is used as a tocolytic, but clinical efficacy has been seriously questioned. Our objective was to use controlled ex vivo conditions and known pregnancy stages, to investigate how 2 key factors, hormones and gestation, affect magnesium's tocolytic ability. We hypothesized that these factors could underlie the varying clinical findings around magnesium's efficacy. Myometrial strips were obtained from nonpregnant (n = 10), mid-pregnant (n = 12), and term-pregnant (n = 11) mouse uterus. The strips were mounted in organ baths superfused with oxygenated physiological saline at pH 7.4 and 37 °C. The effect of different concentrations of MgSO4 (2-20 mM) was examined on spontaneous and oxytocin-induced (0.5-1 nM) contractions. Contractile properties (amplitude, frequency, and area under the curve) were measured before and after application of magnesium. Magnesium sulfate had a dose-dependent inhibitory effect on both spontaneous and oxytocin-induced contractions but was less effective in the presence of oxytocin. In spontaneous contractions, magnesium was more potent as gestation progressed (P < .0001). In the presence of oxytocin, however, there were no significant gestational differences in its effects on contraction. The rapid onset and reversal of magnesium's effects suggest an extracellular action on calcium entry. Taken together, we conclude that magnesium's actions are influenced by both gestational state and hormones, such that, at least in mice, it is least effective in early gestation with oxytocin present and most effective at term in the absence of oxytocin. That magnesium is least effective preterm and oxytocin decreases its effectiveness throughout gestation, may explain its disappointing clinical effects as a tocolytic.
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Affiliation(s)
- Blessing E Osaghae
- Department of Molecular and Cellular Physiology, University Department, Harris-Wellbeing Preterm Birth Research Centre, Institute of Translational Medicine, University of Liverpool, First floor Liverpool Women's Hospital, Crown Street, Liverpool, L8 7SS, UK
| | - Sarah Arrowsmith
- Department of Molecular and Cellular Physiology, University Department, Harris-Wellbeing Preterm Birth Research Centre, Institute of Translational Medicine, University of Liverpool, First floor Liverpool Women's Hospital, Crown Street, Liverpool, L8 7SS, UK
| | - Susan Wray
- Department of Molecular and Cellular Physiology, University Department, Harris-Wellbeing Preterm Birth Research Centre, Institute of Translational Medicine, University of Liverpool, First floor Liverpool Women's Hospital, Crown Street, Liverpool, L8 7SS, UK.
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Butler TA, Paul JW, Smith R. Non-conventional signalling in human myometrium by conventional pathways: looking back for a synergistic future. Current Opinion in Physiology 2020. [DOI: 10.1016/j.cophys.2019.11.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Moen V, Brudin L, Ebberyd A, Sennström M, Ekman-Ordeberg G, Rundgren M, Irestedt L. Hyponatraemia reversibly affects human myometrial contractility. An in vitro pilot study. PLoS One 2020; 15:e0220020. [PMID: 31971939 DOI: 10.1371/journal.pone.0220020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 12/14/2019] [Indexed: 11/19/2022] Open
Abstract
Background In a previous study we found a significant correlation between dystocia and hyponatraemia that developed during labour. The present study examined a possible causal relationship. In vitro studies often use area under the curve (AUC) determined by frequency and force of contractions as a measure of myometrial contractility. However, a phase portrait plot of isometric contraction, obtained by plotting the first derivate of contraction against force of contraction, could indicate that bi-or multiphasic contractions might be less effective compared to the smooth contractions. Material and methods Myometrial biopsies were obtained from 17 women undergoing elective caesarean section at term. Each biopsy was divided into 8 strips and mounted isometrically in a force transducer. Seven biopsies were used in the first part of the study when half of the strips were immersed in the hyponatraemic study solution S containing Na+ 120 mmol/L and observed for 1 hour, followed by 1 hour in normonatraemic control solution C containing Na+ 136 mmol/L, then again in S for 1 hour, and finally 1 hour in C. The other half of the strips were studied in reverse order, C-S-C-S. The remaining ten biopsies were included in the second part of the study. Response to increasing doses of oxytocin (OT) in solutions S and C was studied. In the first part of the study we calculated AUC, and created phase portrait plots of two different contractions from the same strip, one smooth and one biphasic. In both parts of the study we registered frequency and force of contractions, and described appearance of the contractions. Results First part of the study: Mean (median) contractions per hour in C: 8.7 (7.6), in S 14,3 (13). Mean (SD) difference between groups 5.6 (4.2), p = 0.018. Force of contractions in C: 11.8 (10.2) mN, in S: 10.8 (9.2) mN, p = 0.09, AUC increased in S; p = 0.018. Bi-/multiphasic contractions increased from 8% in C to 18% in S, p = 0.001. All changes were reversible in C. Second part of the study: Frequency after OT 1.65 x 10−9 M in C:3.4 (2.9), in S: 3.8 (3.2), difference between groups: p = 0.48. After OT 1.65 x 10−7 M in C: 7.8 (8.9), increase from previous OT administration: p = 0.09, in S: 8.7 (9.0), p = 0.04, difference between groups, p = 0.32. Only at the highest dose of OT dose was there an increase in force of contraction in S, p = 0.05, difference between groups, p = 0.33. Initial response to OT was more frequently bi/multiphasic in S, reaching significance at the highest dose of OT(1.65 x 10−7 M), p = 0.015. when almost all contractions were bi/multiphasic. Conclusion Hyponatraemia reversibly increased frequency of contractions and appearance of bi-or multiphasic contractions, that could reduce myometrial contractility. This could explain the correlation of hyponatraemia and instrumental delivery previously observed. Contractions in the hyponatraemic solution more frequently showed initial multiphasic contractions when OT was added in increasing doses. Longer lasting labours carry the risk both of hyponatraemia and OT administration, and their negative interaction could be significant. Further studies should address this possibility.
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Bravo-Sagua R, Parra V, Muñoz-Cordova F, Sanchez-Aguilera P, Garrido V, Contreras-Ferrat A, Chiong M, Lavandero S. Sarcoplasmic reticulum and calcium signaling in muscle cells: Homeostasis and disease. Int Rev Cell Mol Biol 2020; 350:197-264. [PMID: 32138900 DOI: 10.1016/bs.ircmb.2019.12.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The sarco/endoplasmic reticulum is an extensive, dynamic and heterogeneous membranous network that fulfills multiple homeostatic functions. Among them, it compartmentalizes, stores and releases calcium within the intracellular space. In the case of muscle cells, calcium released from the sarco/endoplasmic reticulum in the vicinity of the contractile machinery induces cell contraction. Furthermore, sarco/endoplasmic reticulum-derived calcium also regulates gene transcription in the nucleus, energy metabolism in mitochondria and cytosolic signaling pathways. These diverse and overlapping processes require a highly complex fine-tuning that the sarco/endoplasmic reticulum provides by means of its numerous tubules and cisternae, specialized domains and contacts with other organelles. The sarco/endoplasmic reticulum also possesses a rich calcium-handling machinery, functionally coupled to both contraction-inducing stimuli and the contractile apparatus. Such is the importance of the sarco/endoplasmic reticulum for muscle cell physiology, that alterations in its structure, function or its calcium-handling machinery are intimately associated with the development of cardiometabolic diseases. Cardiac hypertrophy, insulin resistance and arterial hypertension are age-related pathologies with a common mechanism at the muscle cell level: the accumulation of damaged proteins at the sarco/endoplasmic reticulum induces a stress response condition termed endoplasmic reticulum stress, which impairs proper organelle function, ultimately leading to pathogenesis.
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Pereyra S, Sosa C, Bertoni B, Sapiro R. Transcriptomic analysis of fetal membranes reveals pathways involved in preterm birth. BMC Med Genomics 2019; 12:53. [PMID: 30935390 PMCID: PMC6444860 DOI: 10.1186/s12920-019-0498-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 03/10/2019] [Indexed: 12/21/2022] Open
Abstract
Background Preterm birth (PTB), defined as infant delivery before 37 weeks of completed gestation, results from the interaction of both genetic and environmental components and constitutes a complex multifactorial syndrome. Transcriptome analysis of PTB has proven challenging because of the multiple causes of PTB and the numerous maternal and fetal gestational tissues that must interact to facilitate parturition. The transcriptome of the chorioamnion membranes at the site of rupture in PTB and term fetuses may reflect the molecular pathways of preterm labor. Methods In this work, chorioamnion membranes from severe preterm and term fetuses were analyzed using RNA sequencing. Functional annotations and pathway analysis of differentially expressed genes were performed with the GAGE and GOSeq packages. A subset of differentially expressed genes in PTB was validated in a larger cohort using qRT-PCR and by comparing our results with genes and pathways previously reported in the literature. Results A total of 270 genes were differentially expressed (DE): 252 were upregulated and 18 were down-regulated in severe preterm births relative to term births. Inflammatory and immunological pathways were upregulated in PTB. Both types of pathways were previously suggested to lead to PTB. Pathways that were not previously reported in PTB, such as the hemopoietic pathway, appeared upregulated in preterm membranes. A group of 18 downregulated genes discriminated between term and severe preterm cases. These genes potentially characterize a severe preterm transcriptome pattern and therefore are candidate genes for understanding the syndrome. Some of the downregulated genes are involved in the nervous system, morphogenesis (WNT1, DLX5, PAPPA2) and ion channel complexes (KCNJ16, KCNB1), making them good candidates as biomarkers of PTB. Conclusions The identification of this DE gene pattern will help with the development of a multi-gene disease classifier. These markers were generated in an admixed South American population in which PTB has a high incidence. Since the genetic background may differentially impact different populations, it is necessary to include populations such as those from South America and Africa, which are usually excluded from high-throughput approaches. These classifiers should be compared to those in other populations to obtain a global landscape of PTB. Electronic supplementary material The online version of this article (10.1186/s12920-019-0498-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Silvana Pereyra
- Departamento de Genética, Facultad de Medicina, Universidad de la República, Av. General Flores 2125, C.P, 11800, Montevideo, Uruguay
| | - Claudio Sosa
- Clínica Ginecotologica "C", Centro Hospitalario Pereira Rossell, Facultad de Medicina, Universidad de la República, Bvar. General Artigas 1590, C:P.11600, Montevideo, Uruguay
| | - Bernardo Bertoni
- Departamento de Genética, Facultad de Medicina, Universidad de la República, Av. General Flores 2125, C.P, 11800, Montevideo, Uruguay
| | - Rossana Sapiro
- Departamento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Av. General Flores 2125, C.P, 11800, Montevideo, Uruguay.
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Osaghae BE, Arrowsmith S, Wray S. Gestational and Hormonal Effects on Magnesium Sulfate's Ability to Inhibit Mouse Uterine Contractility. Reprod Sci 2019:1933719119828089. [PMID: 30773125 DOI: 10.1177/1933719119828089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Magnesium sulfate is used as a tocolytic, but clinical efficacy has been seriously questioned. Our objective was to use controlled ex vivo conditions and known pregnancy stages, to investigate how 2 key factors, hormones and gestation, affect magnesium's tocolytic ability. We hypothesized that these factors could underlie the varying clinical findings around magnesium's efficacy. Myometrial strips were obtained from nonpregnant (n = 10), mid-pregnant (n = 12), and term-pregnant (n = 11) mouse uterus. The strips were mounted in organ baths superfused with oxygenated physiological saline at pH 7.4 and 37°C. The effect of different concentrations of MgSO4 (2-20 mM) was examined on spontaneous and oxytocin-induced (0.5-1 nM) contractions. Contractile properties (amplitude, frequency, and area under the curve) were measured before and after application of magnesium. Magnesium sulfate had a dose-dependent inhibitory effect on both spontaneous and oxytocin-induced contractions but was less effective in the presence of oxytocin. In spontaneous contractions, magnesium was more potent as gestation progressed ( P < .0001). In the presence of oxytocin, however, there were no significant gestational differences in its effects on contraction. The rapid onset and reversal of magnesium's effects suggest an extracellular action on calcium entry. Taken together, we conclude that magnesium's actions are influenced by both gestational state and hormones, such that, at least in mice, it is least effective in early gestation with oxytocin present and most effective at term in the absence of oxytocin. That magnesium is least effective preterm and oxytocin decreases its effectiveness throughout gestation, may explain its disappointing clinical effects as a tocolytic.
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Affiliation(s)
- Blessing E Osaghae
- 1 Department of Cellular and Molecular Physiology, University Department, Harris-Wellbeing Preterm Birth Research Centre, The Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Sarah Arrowsmith
- 1 Department of Cellular and Molecular Physiology, University Department, Harris-Wellbeing Preterm Birth Research Centre, The Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Susan Wray
- 1 Department of Cellular and Molecular Physiology, University Department, Harris-Wellbeing Preterm Birth Research Centre, The Institute of Translational Medicine, University of Liverpool, Liverpool, UK
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Domino M, Domino K, Pawlinski B, Sady M, Gajewska M, Gajewski Z. Computational multivariate modelling of electrical activity of the porcine uterus during spontaneous and hormone-induced oestrus. Exp Physiol 2019; 104:322-333. [PMID: 30615243 DOI: 10.1113/ep087451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 01/03/2019] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Does oestrous cycle synchronization influence myoelectrical activity of porcine myometrium? What is the main finding and its importance? Exogenous hormones used to synchronize oestrus in pigs altered myoelectrical activity, which was effectively modelled. Higher-order multivariate statistic modelling provided evidence of similar activity in both types of oestrus, but a larger order of EMG signals during induced oestrus. Higher-order statistical analysis of the probabilistic model suggests the beginning of the early follicular phase and the mid-luteal phase to be most important in evaluation of the natural patterns of myoelectrical activity. Higher-order multivariate cumulants are more informative than classical statistics in characterization of myoelectrical activity changes in porcine myometrium. ABSTRACT In pig production units, control of the oestrous cycle and synchronization of ovulation have become routine herd management procedures. During the oestrous cycle, in both induced and spontaneous conditions, the ovaries and the uterus undergo hormone-dominated physiological changes, which are consistent with the hypothesis that there is a functional role of uterine contractions in promoting fertilization. We have used electromyography to determine whether the use of exogenous hormones, such as equine chorionic gonadotrophin and human chorionic gonadotrophin, which have the potential to control the timing of ovulation in female pigs, changes the multivariate relationships between parameters of electrical bursts and modulates the patterns of myoelectrical activity. We used the mathematical approach of higher-order multivariate cumulants in complex modelling of the myometrial electrical activity. The experiment was conducted on 12 mature Polish Landrace sows, and uterine activity was recorded during both spontaneous and induced oestrous cycles. The burst parameters were determined using six features in the time domain and, after Fast Fourier transformation, in the frequency domain. Evaluation of myoelectrical activity patterns was conducted based on classical univariate statistical methods and multivariate probabilistic modelling. The classical statistical approach indicated weaker myoelectrical activity after hormonal stimulation, whereas the higher-order multivariate statistical model showed evidence of similar status of activity and a larger order of signals during induced oestrus. Routine oestrous cycle synchronization affects the multivariate probabilistic model of myometrial electrical activity.
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Affiliation(s)
- Malgorzata Domino
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - Szkola Glowna Gospodarstwa Wiejskiego, Nowoursynowska 100, 02-797, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Krzysztof Domino
- Institute of Theoretical and Applied Informatics, Polish Academy of Sciences, Bałtycka 5, 44-100, Gliwice, Poland
| | - Bartosz Pawlinski
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - Szkola Glowna Gospodarstwa Wiejskiego, Nowoursynowska 100, 02-797, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Maria Sady
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - Szkola Glowna Gospodarstwa Wiejskiego, Nowoursynowska 100, 02-797, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Magdalena Gajewska
- Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Nowoursynowska 100, 02-797, Warsaw, Poland
| | - Zdzislaw Gajewski
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - Szkola Glowna Gospodarstwa Wiejskiego, Nowoursynowska 100, 02-797, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Nowoursynowska 100, 02-797, Warsaw, Poland
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20
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Sarker MAK, Aki S, Yoshioka K, Kuno K, Okamoto Y, Ishimaru K, Takuwa N, Takuwa Y. Class II PI3Ks α and β Are Required for Rho-Dependent Uterine Smooth Muscle Contraction and Parturition in Mice. Endocrinology 2019; 160:235-248. [PMID: 30476019 DOI: 10.1210/en.2018-00756] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 11/15/2018] [Indexed: 11/19/2022]
Abstract
Class II phosphoinositide 3-kinases (PI3Ks), PI3K-C2α and PI3K-C2β, are highly homologous and distinct from class I and class III PI3Ks in catalytic products and domain structures. In contrast to class I and class III PI3Ks, physiological roles of PI3K-C2α and PI3K-C2β are not fully understood. Because we previously demonstrated that PI3K-C2α is involved in vascular smooth muscle contraction, we studied the phenotypes of smooth muscle-specific knockout (KO) mice of PI3K-C2α and PI3K-C2β. The pup numbers born from single PI3K-C2α-KO and single PI3K-C2β-KO mothers were similar to those of control mothers, but those from double KO (DKO) mothers were smaller compared with control mice. However, the number of intrauterine fetuses in pregnant DKO mothers was similar to that in control mice. Both spontaneous and oxytocin-induced contraction of isolated uterine smooth muscle (USM) strips was diminished in DKO mice but not in either of the single KO mice, compared with control mice. Furthermore, contraction of USM of DKO mice was less sensitive to a Rho kinase inhibitor. Mechanistically, the extent of oxytocin-induced myosin light chain phosphorylation was greatly reduced in USM from DKO mice compared with control mice. The oxytocin-induced rise in the intracellular Ca2+ concentration in USM was similar in DKO and control mice. However, Rho activation in the intracellular compartment was substantially attenuated in DKO mice compared with control mice, as evaluated by fluorescence resonance energy transfer imaging technique. These data indicate that both PI3K-C2α and PI3K-C2β are required for normal USM contraction and parturition mainly through their involvement in Rho activation.
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Affiliation(s)
| | - Sho Aki
- Department of Physiology, Kanazawa University School of Medicine, Kanazawa, Japan
| | - Kazuaki Yoshioka
- Department of Physiology, Kanazawa University School of Medicine, Kanazawa, Japan
| | - Kouji Kuno
- Cancer Research Institute, Kanazawa University, Kanazawa, Japan
| | - Yasuo Okamoto
- Department of Physiology, Kanazawa University School of Medicine, Kanazawa, Japan
| | - Kazuhiro Ishimaru
- Department of Physiology, Kanazawa University School of Medicine, Kanazawa, Japan
| | - Noriko Takuwa
- Department of Health Science, Ishikawa Prefectural University, Kahoku, Japan
| | - Yoh Takuwa
- Department of Physiology, Kanazawa University School of Medicine, Kanazawa, Japan
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Domino M, Domino K, Gajewski Z. An application of higher order multivariate cumulants in modelling of myoelectrical activity of porcine uterus during early pregnancy. Biosystems 2018; 175:30-38. [PMID: 30391263 DOI: 10.1016/j.biosystems.2018.10.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 10/29/2018] [Accepted: 10/30/2018] [Indexed: 01/18/2023]
Abstract
The analysis of the uterine contraction have become a general practice in an effort to improve the clinical management of uterine contractions during pregnancy and labour in human beings. The fluctuations in uterine activity may occur without affecting progress of gestation, however the painful and fashion contractions may be the first threat of miscarriage. While pigs were considered as an referential preclinical model, the computational modelling of spontaneous myoelectrical activity of complex systems of porcine myometrium in peri-fertilization period has been proposed. The higher order statistic, multivariate cumulants and Joint Skewness Band Selection method, have been applied to study the dependence structure of electromyographic (EMG) signal with an effective EMG feature. Than the model of recognition of multivariate, myoelectricaly changes according to crucial stages for successful fertilization and early pregnancy maintenance has been estimated. We found that considering together time and frequency features of EMG signal was extremely non-Gaussian distributed and the higher order multivariate statistics such as cumulants, have to be used to determine the pattern of myoelectrical activity in reproductive tract. We confirmed the expectance that the probabilistic model changes on a daily base. We demonstrated the changes in proposed model at the crucial time points of in peri-fertilization period. We speculate the activity of the middle of uterine horn and the power (minimum and maximum) and pauses between myoelectrical burst features are essential for the functional role of uterine contractility in peri-fertilization period.
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Affiliation(s)
- Malgorzata Domino
- Department of Large Animal Diseases with Clinic, Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Warsaw, Poland
| | - Krzysztof Domino
- Institute of Theoretical and Applied Informatics, Polish Academy of Sciences, Gliwice, Poland
| | - Zdzislaw Gajewski
- Department of Large Animal Diseases with Clinic, Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Warsaw, Poland.
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Karacin O, Mutlu I, Kose M, Celik F, Kanat-Pektas M, Yilmazer M. Serum vitamin D concentrations in young Turkish women with primary dysmenorrhea: A randomized controlled study. Taiwan J Obstet Gynecol 2018; 57:58-63. [PMID: 29458904 DOI: 10.1016/j.tjog.2017.12.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2016] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE This study aims to investigate the possible role of vitamin D deficiency in primary dysmenorrhea by assessing serum 25-hydroxyvitamin D3 levels in a cohort which includes young Turkish women with primary dysmenorrhea and healthy controls. MATERIALS AND METHODS A total of 683 women who were aged between 18 and 25 years and who were consecutively admitted to the study center were eligible. After the exclusion of 55 women, 184 women with primary dysmenorrhea were randomly assigned into the dysmenorrhea group and 184 women without dysmenorrhea were randomly allocated into the control group. RESULTS The dysmenorrhea group had significantly less consumption of dairy products (p = 0.001), lower serum calcium (p = 0.001), lower serum vitamin D (p = 0.001) and higher serum parathyroid hormone (p = 0.001) than those of the control group. Hyperparathyroidism was significantly less frequent whereas vitamin D deficiency was significantly more frequent in the dysmenorrhea group (p = 0.001 for each). The dysmenorrhea patients with vitamin D deficiency had significantly higher visual analogue scale (VAS) scores (p = 0.001). Depression, irritability, mood swings, fatigue, headache and breast tenderness were significantly more frequent in the vitamin D deficiency group (p < 0.05 for all). The VAS scores of the dysmenorrhea patients correlated positively and significantly with serum parathyroid hormone levels (r = 0.666, p = 0.001) whereas these VAS scores correlated negatively and significantly with serum vitamin D levels (r = -0.713, p = 0.001). DISCUSSION The significant and positive correlation between vitamin D levels and VAS scores and the significant reduction in serum vitamin D levels of the dysmenorrhea patients designate the possible role of vitamin D deficiency in the primary dysmenorrhea.
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Affiliation(s)
- Osman Karacin
- Department of Obstetrics and Gynecology, Afyon Kocatepe University Hospital, Afyonkarahisar, Turkey
| | - Ilknur Mutlu
- Department of Obstetrics and Gynecology, Novaart In Vitro Fertilization Center, Ankara, Turkey
| | - Mesut Kose
- Department of Obstetrics and Gynecology, Afyon Kocatepe University Hospital, Afyonkarahisar, Turkey
| | - Fatih Celik
- Department of Obstetrics and Gynecology, Afyon Kocatepe University Hospital, Afyonkarahisar, Turkey
| | - Mine Kanat-Pektas
- Department of Obstetrics and Gynecology, Afyon Kocatepe University Hospital, Afyonkarahisar, Turkey.
| | - Mehmet Yilmazer
- Department of Obstetrics and Gynecology, Afyon Kocatepe University Hospital, Afyonkarahisar, Turkey
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Floyd RV, Mobasheri A, Wray S. Gestation changes sodium pump isoform expression, leading to changes in ouabain sensitivity, contractility, and intracellular calcium in rat uterus. Physiol Rep 2018; 5. [PMID: 29208689 PMCID: PMC5727280 DOI: 10.14814/phy2.13527] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 10/30/2017] [Accepted: 11/01/2017] [Indexed: 11/24/2022] Open
Abstract
Developmental and tissue‐specific differences in isoforms allow Na+, K+‐ATPase function to be tightly regulated, as they control sensitivity to ions and inhibitors. Uterine contraction relies on the activity of the Na+, K+ATPase, which creates ionic gradients that drive excitation‐contraction coupling. It is unknown whether Na+, K+ATPase isoforms are regulated throughout pregnancy or whether they have a direct role in modulating uterine contractility. We hypothesized that gestation‐dependent differential expression of isoforms would affect contractile responses to Na+, K+ATPase α subunit inhibition with ouabain. Our aims were therefore: (1) to determine the gestation‐dependent expression of mRNA transcripts, protein abundance and tissue distribution of Na+, K+ATPase isoforms in myometrium; (2) to investigate the functional effects of differential isoform expression via ouabain sensitivity; and (3) if changes in contractile responses can be explained by changes in intracellular [Ca2+]. Changes in abundance and distribution of the Na+, K+ATPase α, β and FXYD1 and 2 isoforms, were studied in rat uterus from nonpregnant, and early, mid‐, and term gestation. All α, β subunit isoforms (1,2,3) and FXYD1 were detected but FXYD2 was absent. The α1 and β1 isoforms were unchanged throughout pregnancy, whereas α2 and α3 significant decreased at term while β2 and FXYD1 significantly increased from mid‐term onwards. These changes in expression correlated with increased functional sensitivity to ouabain, and parallel changes in intracellular Ca2+, measured with Indo‐1. In conclusion, gestation induces specific regulatory changes in expression of Na+, K+ATPase isoforms in the uterus which influence contractility and may be related to the physiological requirements for successful pregnancy and delivery.
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Affiliation(s)
- Rachel V Floyd
- The Department of Molecular and Cellular Physiology, University of Liverpool, Liverpool, United Kingdom
| | - Ali Mobasheri
- Department of Veterinary Preclinical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Susan Wray
- The Department of Molecular and Cellular Physiology, University of Liverpool, Liverpool, United Kingdom
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Banciu A, Banciu DD, Mustaciosu CC, Radu M, Cretoiu D, Xiao J, Cretoiu SM, Suciu N, Radu BM. Beta-Estradiol Regulates Voltage-Gated Calcium Channels and Estrogen Receptors in Telocytes from Human Myometrium. Int J Mol Sci 2018; 19:E1413. [PMID: 29747396 DOI: 10.3390/ijms19051413] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/14/2018] [Accepted: 05/02/2018] [Indexed: 12/18/2022] Open
Abstract
Voltage-gated calcium channels and estrogen receptors are essential players in uterine physiology, and their association with different calcium signaling pathways contributes to healthy and pathological conditions of the uterine myometrium. Among the properties of the various cell subtypes present in human uterine myometrium, there is increasing evidence that calcium oscillations in telocytes (TCs) contribute to contractile activity and pregnancy. Our study aimed to evaluate the effects of beta-estradiol on voltage-gated calcium channels and estrogen receptors in TCs from human uterine myometrium and to understand their role in pregnancy. For this purpose, we employed patch-clamp recordings, ratiometric Fura-2-based calcium imaging analysis, and qRT-PCR techniques for the analysis of cultured human myometrial TCs derived from pregnant and non-pregnant uterine samples. In human myometrial TCs from both non-pregnant and pregnant uterus, we evidenced by qRT-PCR the presence of genes encoding for voltage-gated calcium channels (Cav3.1, Ca3.2, Cav3.3, Cav2.1), estrogen receptors (ESR1, ESR2, GPR30), and nuclear receptor coactivator 3 (NCOA3). Pregnancy significantly upregulated Cav3.1 and downregulated Cav3.2, Cav3.3, ESR1, ESR2, and NCOA3, compared to the non-pregnant condition. Beta-estradiol treatment (24 h, 10, 100, 1000 nM) downregulated Cav3.2, Cav3.3, Cav1.2, ESR1, ESR2, GRP30, and NCOA3 in TCs from human pregnant uterine myometrium. We also confirmed the functional expression of voltage-gated calcium channels by patch-clamp recordings and calcium imaging analysis of TCs from pregnant human myometrium by perfusing with BAY K8644, which induced calcium influx through these channels. Additionally, we demonstrated that beta-estradiol (1000 nM) antagonized the effect of BAY K8644 (2.5 or 5 µM) in the same preparations. In conclusion, we evidenced the presence of voltage-gated calcium channels and estrogen receptors in TCs from non-pregnant and pregnant human uterine myometrium and their gene expression regulation by beta-estradiol in pregnant conditions. Further exploration of the calcium signaling in TCs and its modulation by estrogen hormones will contribute to the understanding of labor and pregnancy mechanisms and to the development of effective strategies to reduce the risk of premature birth.
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Li W, Sasse KC, Bayguinov Y, Ward SM, Perrino BA. Contractile Protein Expression and Phosphorylation and Contractility of Gastric Smooth Muscles from Obese Patients and Patients with Obesity and Diabetes. J Diabetes Res 2018; 2018:8743874. [PMID: 29955616 PMCID: PMC6000859 DOI: 10.1155/2018/8743874] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/11/2018] [Accepted: 04/18/2018] [Indexed: 12/22/2022] Open
Abstract
Ingested food is received, mixed, and ground into chyme by distinct gastric motility patterns. Diabetes impairs gastric muscle function, but the mechanisms underlying diabetes-induced gastric muscle dysfunction are unknown. Here, we compared the expression and phosphorylation of Ca2+ sensitization and contractile proteins in human gastric muscles from obese nondiabetic and diabetic patients. We also compared the spontaneous phasic contractions and the contractile responses evoked by electrical field stimulation of cholinergic motor neurons. Fundus and antrum muscles were obtained from sleeve gastrectomies and were used in in vitro myobath contractile studies and for capillary electrophoresis and immunodetection of γ-actin, CPI-17, pT38-CPI-17, MYPT1, pT853-MYPT1, pT696-MYPT1, myosin light chain (MYL9), pS19-MYL9, myosin light chain kinase (MYLK), protein phosphatase-1δ (PP1δ), and Rho-associated kinase (ROCK2). In diabetic fundus muscles, MYLK, ROCK2, and PP1δ expression was unchanged; MYPT1 and CPI-17 expression was decreased; and the pT853/MYPT1 and pT38/CPI-17 ratios, but not the pT696/MYPT1 ratio, were increased. Although MYL9 expression was increased, the pS19/MYL9 ratio was unchanged in diabetic fundus muscles. In diabetic antrum muscles, MYLK and MYL9 expression was unchanged, but ROCK2, CPI-17, and PP1δ expression was decreased. The pT38/CPI-17 ratio was unchanged, while the pS19/MYL9, pT853/MYPT1, and pT696/MYPT1 ratios were decreased, consistent with the reduced ROCK2 expression. The frequencies of spontaneous phasic contractions from nondiabetic and diabetic gastric fundus and antrum muscles did not significantly differ from each other, regardless of age, sex, or diabetic status. The fold increases in the contractions of diabetic fundus and antrum muscles in response to increased frequencies of electrical field stimulation were significantly lower compared to nondiabetic fundus and antrum muscles. The altered contractile responses and the protein expression and phosphorylation in gastric muscles of obese patients with diabetes illustrate the importance of understanding how smooth muscle Ca2+ sensitization mechanisms contribute to gastric motility.
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Affiliation(s)
- Wen Li
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Kent C. Sasse
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
- Sasse Surgical Associates, Reno NV 89502, USA
- Renown Regional Medical Center, Reno, NV 89502, USA
| | - Yulia Bayguinov
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Sean M. Ward
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Brian A. Perrino
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
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Pawlinski B, Domino M, Zabielski R, Siewruk K, Polanska-Plachta M, Gajewski Z. Characteristics of bioelectrical activity of oviducts and uterus during early pregnancy in sows recorded by telemetry method. Exp Physiol 2017; 102:1672-1682. [PMID: 28940594 DOI: 10.1113/ep086491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/05/2017] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? The aim of present study was to record and analyse the myoelectrical activity in the female pig reproductive tract (uterus and oviduct) during early pregnancy. What is the main finding and its importance? Understanding the contractile activity of the uterus and oviducts is indispensable for understanding the physiological mechanisms as well as all irregularities associated with the period of conception and early pregnancy. The aim of the present study was to record the myoelectrical activity of the reproductive tract in sows during the oestrous phase and early pregnancy via a telemetry recording system. In a total of eight non-pregnant pigs, the bioelectrical activity was recorded through three silicone electrodes sutured on the oviduct (isthmus and ampulla) and the uterine horn. Blood samples were collected to monitor the concentrations of progesterone (P4) and luteinizing hormone (LH). The oestrous cycle was synchronized with equine chorionic gonadotrophin (eCG) and human chorionic gonadotrophin (hCG), and the animals were subjected to artificial insemination. Analysis of the EMG activity of the oviduct and uterus in the oestrous phase and in early stages of pregnancy suggests explicitly that telemetry could enable in vivo assessment of myoelectrical activity of parts of the reproductive system in sows. Off-line analysis of the duration of EMG activity bursts in the uterus, isthmus and ampulla were significantly higher during early pregnancy (phases II and III) than in the oestrous phase. The EMG signals demonstrated low mean amplitudes of activity in the oviduct and uterus during early pregnancy (phases I-III). Significant differences between the root mean square signals were observed in the isthmus and ampulla both during oestrus and in early pregnancy (phase I; P < 0.01). During the oestrous phase, the P4 concentration was estimated at <1 ng ml-1 , whereas the LH concentration was >4 ng ml-1 . In contrast, during early pregnancy, the P4 and LH concentrations were estimated at >4 and <1 ng ml-1 , respectively.
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Affiliation(s)
- Bartosz Pawlinski
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland
| | - Malgorzata Domino
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland
| | - Romuald Zabielski
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland
| | - Katarzyna Siewruk
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland
| | - Malgorzata Polanska-Plachta
- 2nd Department of General, Vascular and Oncologic Surgery, 2nd Faculty of Medicine with English Division and Physiotherapy Division, MUW, Czerniakowski Hospital, Warszawa, Poland
| | - Zdzislaw Gajewski
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland.,Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Warsaw, Poland
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27
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Westervelt AR, Fernandez M, House M, Vink J, Nhan-Chang CL, Wapner R, Myers KM. A Parameterized Ultrasound-Based Finite Element Analysis of the Mechanical Environment of Pregnancy. J Biomech Eng 2017; 139:2612939. [PMID: 28303276 DOI: 10.1115/1.4036259] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Indexed: 11/08/2022]
Abstract
Preterm birth is the leading cause of childhood mortality and can lead to health risks in survivors. The mechanical functions of the uterus, fetal membranes, and cervix have dynamic roles to protect the fetus during gestation. To understand their mechanical function and relation to preterm birth, we built a three-dimensional parameterized finite element model of pregnancy. This model is generated by an automated procedure that is informed by maternal ultrasound measurements. A baseline model at 25 weeks of gestation was characterized, and to visualize the impact of cervical structural parameters on tissue stretch, we evaluated the model sensitivity to (1) anterior uterocervical angle, (2) cervical length, (3) posterior cervical offset, and (4) cervical stiffness. We found that cervical tissue stretching is minimal when the cervical canal is aligned with the longitudinal uterine axis, and a softer cervix is more sensitive to changes in the geometric variables tested.
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Affiliation(s)
- Andrea R Westervelt
- Department of Mechanical Engineering, Columbia University, New York, NY 10027 e-mail:
| | - Michael Fernandez
- Department of Mechanical Engineering, Columbia University, New York, NY 10027 e-mail:
| | - Michael House
- Department of Obstetrics and Gynecology, Tufts Medical Center, Boston, MA 02111 e-mail:
| | - Joy Vink
- Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY 10032 e-mail:
| | - Chia-Ling Nhan-Chang
- Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY 10032 e-mail:
| | - Ronald Wapner
- Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY 10032 e-mail:
| | - Kristin M Myers
- Mem. ASME Department of Mechanical Engineering, Columbia University, New York, NY 10027 e-mail:
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28
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Myers KM, Elad D. Biomechanics of the human uterus. Wiley Interdiscip Rev Syst Biol Med 2017; 9. [PMID: 28498625 DOI: 10.1002/wsbm.1388] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 02/23/2017] [Accepted: 03/01/2017] [Indexed: 12/15/2022]
Abstract
The appropriate biomechanical function of the uterus is required for the execution of human reproduction. These functions range from aiding the transport of the embryo to the implantation site, to remodeling its tissue walls to host the placenta, to protecting the fetus during gestation, to contracting forcefully for a safe parturition and postpartum, to remodeling back to its nonpregnant condition to renew the cycle of menstruation. To serve these remarkably diverse functions, the uterus is optimally geared with evolving and contractile muscle and tissue layers that are cued by chemical, hormonal, electrical, and mechanical signals. The relationship between these highly active biological signaling mechanisms and uterine biomechanical function is not completely understood for normal reproductive processes and pathological conditions such as adenomyosis, endometriosis, infertility and preterm labor. Animal studies have illuminated the rich structural function of the uterus, particularly in pregnancy. In humans, medical imaging techniques in ultrasound and magnetic resonance have been combined with computational engineering techniques to characterize the uterus in vivo, and advanced experimental techniques have explored uterine function using ex vivo tissue samples. The collective evidence presented in this review gives an overall perspective on uterine biomechanics related to both its nonpregnant and pregnant function, highlighting open research topics in the field. Additionally, uterine disease and infertility are discussed in the context of tissue injury and repair processes and the role of computational modeling in uncovering etiologies of disease. WIREs Syst Biol Med 2017, 9:e1388. doi: 10.1002/wsbm.1388 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Kristin M Myers
- Department of Mechanical Engineering, Columbia University, New York, NY, USA
| | - David Elad
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel.,Department of Biomedical Engineering, Columbia University, New York, NY, USA
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Gora S, Elad D, Jaffa AJ. Objective Analysis of Vaginal Ultrasound Video Clips for Exploring Uterine Peristalsis Post Vaginal and Cesarean Section Deliveries. Reprod Sci 2017; 25:899-908. [PMID: 28345486 DOI: 10.1177/1933719117697256] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The nonpregnant uterus is characterized by cyclic contractions that assist in sperm transport to the fallopian tube, embryo transport to implantation site, and expulsion of menstrual debris. The effect of post-Cesarean section (CS) scar on uterine peristalsis is unclear, while worldwide the prevalence of CS deliveries is increasing. In this study, we developed a new objective method for analysis of dynamic characteristics of the nonpregnant uterus from transvaginal ultrasound (TVUS) recordings when the uterine cavity is not clearly observed, as may be the case in post-CS uteri. The method of active contours was utilized to detect the contours of the endometrium-myometrium interface (EMI) from sagittal cross-section TVUS images of nonpregnant uteri. The contours were straightened along the uterus centerline and registered with respect to the fundal end in order to reduce the noise due to movements of the physician and the participant. A dynamic analysis was conducted on these time-dependent contours in order to explore the frequency and amplitude of the EMI motility. The analysis was conducted on TVUS video clips from 12 nonpregnant participants, 7 post-CS and 5 controls. The frequencies of the EMI motility was 0.010 to 0.064 Hz at days 8 to 17 in the control participants and 0.014 to 0.073 Hz at days 9 to 15 in post-CS participants. The maximal amplitude of motility was 0.67 to 2.00 mm and 0.48 to 2.58 mm for the control and post-CS participants, respectively. In this preliminary study, we have not observed significant difference between the EMI motility of healthy and post-CS uteri.
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Affiliation(s)
- Silvia Gora
- 1 Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - David Elad
- 1 Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Ariel J Jaffa
- 2 Ultrasound Unit in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,3 Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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30
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Alotaibi M, Kahlat K, Nedjadi T, Djouhri L. Effects of ZD7288, a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blocker, on term-pregnant rat uterine contractility in vitro. Theriogenology 2017; 90:141-146. [DOI: 10.1016/j.theriogenology.2016.11.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 11/22/2016] [Accepted: 11/24/2016] [Indexed: 12/01/2022]
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Affiliation(s)
- P. B. Persson
- Institute of Vegetative Physiology; Charité-Universitaetsmedizin Berlin; Berlin Germany
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32
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Bafor EE, Rowan EG, Edrada-Ebel R. Toward Understanding Myometrial Regulation: Metabolomic Investigation Reveals New Pathways of Oxytocin and Ritodrine Activity on the Myometrium. Reprod Sci 2016; 24:691-705. [DOI: 10.1177/1933719116667224] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Enitome E. Bafor
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, United Kingdom
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Benin, Benin, Edo State, Nigeria
| | - Edward G. Rowan
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, United Kingdom
| | - RuAngelie Edrada-Ebel
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, United Kingdom
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Kyeong KS, Hong SH, Kim YC, Cho W, Myung SC, Lee MY, You RY, Kim CH, Kwon SY, Suzuki H, Park YJ, Jeong EH, Kim HS, Kim H, Lim SW, Xu WX, Lee SJ, Ji IW. Myometrial relaxation of mice via expression of two pore domain acid sensitive K(+) (TASK-2) channels. Korean J Physiol Pharmacol 2016; 20:547-56. [PMID: 27610042 PMCID: PMC5015002 DOI: 10.4196/kjpp.2016.20.5.547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 08/01/2016] [Accepted: 08/08/2016] [Indexed: 11/17/2022]
Abstract
Myometrial relaxation of mouse via expression of two-pore domain acid sensitive (TASK) channels was studied. In our previous report, we suggested that two-pore domain acid-sensing K+ channels (TASK-2) might be one of the candidates for the regulation of uterine circular smooth muscles in mice. In this study, we tried to show the mechanisms of relaxation via TASK-2 channels in marine myometrium. Isometric contraction measurements and patch clamp technique were used to verify TASK conductance in murine myometrium. Western blot and immunehistochemical study under confocal microscopy were used to investigate molecular identity of TASK channel. In this study, we showed that TEA and 4-AP insensitive non-inactivating outward K+ current (NIOK) may be responsible for the quiescence of murine pregnant longitudinal myometrium. The characteristics of NIOK coincided with two-pore domain acid-sensing K+ channels (TASK-2). NIOK in the presence of K+ channel blockers was inhibited further by TASK inhibitors such as quinidine, bupivacaine, lidocaine, and extracellular acidosis. Furthermore, oxytocin and estrogen inhibited NIOK in pregnant myometrium. When compared to non-pregnant myometrium, pregnant myometrium showed stronger inhibition of NIOK by quinidine and increased immunohistochemical expression of TASK-2. Finally, TASK-2 inhibitors induced strong myometrial contraction even in the presence of L-methionine, a known inhibitor of stretch-activated channels in the longitudinal myometrium of mouse. Activation of TASK-2 channels seems to play an essential role for relaxing uterus during pregnancy and it might be one of the alternatives for preventing preterm delivery.
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Affiliation(s)
- Kyu-Sang Kyeong
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Seung Hwa Hong
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Young Chul Kim
- Department Physiology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Woong Cho
- Department of Pharmacology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Sun Chul Myung
- Department of Urology, College of Medicine, Chung-Ang University, Seoul 06974, Korea
| | - Moo Yeol Lee
- Department of Physiology, College of Medicine, Chung-Ang University, Seoul 06974, Korea
| | - Ra Young You
- Department Physiology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Chan Hyung Kim
- Department of Pharmacology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | | | - Hikaru Suzuki
- Department of Physiology, Nagoya City University Medical School, Nagoya 467-8601, Japan
| | - Yeon Jin Park
- Department of Obstetrics and Gynecology, Cheongju St. Mary's Hospital, Cheongju 28323, Korea
| | - Eun-Hwan Jeong
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Hak Soon Kim
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Heon Kim
- Department of Preventive Medicine, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Seung Woon Lim
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Wen-Xie Xu
- Department of Physiology, Shanghai Jiaotong University, School of Medicine, Shanghai, 200240, P.R. China
| | - Sang Jin Lee
- Department of Medical Education, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Il Woon Ji
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
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Pawliński B, Domino M, Aniołek O, Ziecik A, Gajewski Z. Bioelectrical activity of porcine oviduct and uterus during spontaneous and induced estrus associated with cyclic hormone changes. Theriogenology 2016; 86:2312-2322. [PMID: 27590095 DOI: 10.1016/j.theriogenology.2016.07.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 10/21/2022]
Abstract
It is widely accepted that uterine contraction is initiated by spontaneous generation of electrical activity at a cellular level in the form of action potentials. Such action potential events, when they involve many myometrial cells and occur in immediate succession, are described by their amplitude and duration. In an effort to improve clinical management of uterine contractions, research has focused on determination of the properties of the reproductive tract's electrical activity under hormonal stimulation. The aim of this study was to evaluate the myoelectric activity (amplitude and duration) of the oviduct and the uterus in relation to plasma concentration of LH, estradiol (E2), and progesterone (P4) during spontaneous and induced estrus in gilts. The course of the experiment was divided into eight periods defined by hormone concentrations (LH, P4, and E2) and time intervals before and after the start of the LH surge. Myoelectric signals were recorded, and the hormone levels were measured during proestrus and estrus in natural and hormone-induced estrus cycle. During the natural estrus, the LH surge was longer than after hormonal stimulation (28 vs. 20 hours) and suggested an inverse relationship between the LH concentration and the duration of myoelectric activity (SR = -0.68). Analyses of the records of the amplitudes and durations of the electromyography activity in uterine horns and oviducts showed significant differences between spontaneous and induced estrus (P < 0.05). During induced estrus, the LH surge began earlier (T1 vs. T2) and increased more (7.46 vs. 6.50 ng/mL) than during spontaneous estrus. This observation suggests a direct relationship between the LH concentration and the amplitude of the myoelectric activity (Spearman rank correlation = 0.71). The significantly higher duration and amplitude of the activity in the isthmus of the oviduct and the uterus during induced estrus shortly after the onset of standing heat (4-8 hours after the LH surge) suggested more favorable conditions for effective artificial insemination.
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Affiliation(s)
- Bartosz Pawliński
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland; Veterinary Research Centre, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland
| | - Małgorzata Domino
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland; Veterinary Research Centre, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland
| | - Olga Aniołek
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland; Veterinary Research Centre, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland
| | - Adam Ziecik
- Veterinary Research Centre, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland; Department of Hormonal Action Mechanisms, Institute of Animal Reproduction and Food Research of Polish Academy of Sciences, Olsztyn, Poland
| | - Zdzislaw Gajewski
- Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland; Veterinary Research Centre, Faculty of Veterinary Medicine, WULS-SGGW, Warsaw, Poland.
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Young RC. Mechanotransduction mechanisms for coordinating uterine contractions in human labor. Reproduction 2016; 152:R51-61. [PMID: 27165050 DOI: 10.1530/rep-16-0156] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 05/09/2016] [Indexed: 11/08/2022]
Abstract
This review presents evolving concepts of how the human uterus contracts in pregnancy, with emphasis on the mechanisms of long-distance signaling. Action potential propagation has historically been assumed to be the sole mechanism for signaling and tissue recruitment over both short and long distances. However, data in animals and humans indicate that a single action potential does not travel distances greater than a few centimeters. To address this enigma, a long-distance signaling mechanism based on hydraulic signaling and mechanotransduction is developed. By combining this mechanism for long-distance signaling with the action potential propagation mechanism for signaling over short distances, a comprehensive dual mechanism model (or 'dual model') of uterine function is formulated. Mechanotransduction is an accepted phenomenon of myometrium, but the dual model identifies mechanotransduction as relevant to normal labor. For hydraulic signaling, a local contraction slightly increases intrauterine pressure, which globally increases wall tension. Increased wall tension then mechanically induces additional local contractions that further raise pressure. This leads to robust, positive feedback recruitment that explains the emergence of consistently strong contractions of human labor. Three key components of the dual model - rapid long-distance signaling, mechanical triggering, and electrical activity - converge with the concept of mechanically sensitive electrogenic pacemakers distributed throughout the wall. The dual model retains excitation-contraction coupling and action potential propagation for signaling over short distances (<10cm) and hence is an extension of the action potential model rather than a replacement.
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Affiliation(s)
- Roger C Young
- PreTel, Inc.Memphis, TN, USA University of NewcastleNewcastle, Australia Imperial College of LondonChelsea and Westminster Hospital, London, UK
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Lammers WJEP, Stephen B, Al-Sultan MA, Subramanya SB, Blanks AM. The location of pacemakers in the uteri of pregnant guinea pigs and rats. Am J Physiol Regul Integr Comp Physiol 2015; 309:R1439-46. [PMID: 26377559 DOI: 10.1152/ajpregu.00187.2015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 09/01/2015] [Indexed: 01/31/2023]
Abstract
The pregnant uterus is a smooth muscle organ whose pattern of contraction is dictated by the propagation of electrical impulses. Such electrical activity may originate from one or more pacemakers, but the location of these sites has not yet been determined. To detect the location of the pacemaker in the gravid uterus, two approaches were used: 1) determine the site from where the contraction started using isolated uteri from the pregnant guinea pig, and videotape their contractions; and 2) record, in isolated uteri from pregnant term rats, with 240 extracellular electrodes simultaneously, and determine where the electrical bursts started. In both the contractile and electrophysiological experiments, there was not a single, specific pacemaker area. However, most contractions (guinea pig 87%) and bursts (rat 76%) started close to the mesometrial border (mean 2.7 ± 4.0 mm SD in guinea pigs and 1.3 ± 1.4 mm in rats). In addition, in the rat, most sites of initiations were located closer to the ovarial end of the horn (mean distance from the ovarial end 6.0 ± 6.2 mm SD), whereas such an orientation was not seen in the guinea pig. In both guinea pig and rat uteri at term, there is not one specific pacemaker area. Rather, contractile and electrical activity may arise from any site, with the majority starting close to the mesometrial border. Furthermore, in the rat, most activities started at the ovarial end of the horn. This may suggest a slightly different pattern of contraction in both species.
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Affiliation(s)
- Wim J E P Lammers
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; and
| | - Betty Stephen
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; and
| | - Mahmood Ahmed Al-Sultan
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; and
| | - Sandeep B Subramanya
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; and
| | - Andrew M Blanks
- Division of Translational and Systems Medicine, Warwick Medical School, Clinical Sciences Research Laboratory, Coventry, United Kingdom
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Abstract
NEW FINDINGS What is the topic of this review? I focus on clinical aspects of uterine physiology, specifically, myometrial contractility. I bring together and contrast findings using physiological approaches and those using newer techniques, 'omics'. What advances does it highlight? Physiological studies have recently shed light on the myometrium in twin pregnancies, but there have been no 'omic' approaches. In contrast, studies of preterm delivery using newer approaches are generating new research avenues, whereas traditional approaches have not flourished. Finally, I describe significant advances in understanding of 'slow-to-progress' labours, achieved using physiological and clinical approaches. Advances in molecular, genetic and 'omic' technologies are fuelling the thirst for better understanding of the uterus and application of this information to problems in pregnancy and labour. Progress has, however, been limited while we still have an incomplete understanding of some of the basic physiology of uterine smooth muscle (myometrium). In this review and opinion piece, I explore some of the fascinating findings from selected recent studies and see how these may provide new avenues for physiological and clinical research. It is also the case, however, that there is still limited mechanistic understanding about physiological and pathophysiological processes in the myometrium. This lack of understanding limits the usefulness of some findings from genomic and allied studies. By focusing on some key recent findings and relating these to two important clinical problems in childbirth that involve myometrial activity, namely preterm delivery and difficult labours, the interplay between our physiological knowledge and the information provided by newer technologies is explored. My opinion is that physiology has provided much more new mechanistic insight into difficult births and that the newer technologies may lead to breakthroughs in preterm birth research, but that this has not yet happened.
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Affiliation(s)
- Susan Wray
- Harris/Wellbeing Centre for Preterm Birth Research, Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
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Mijušković A, Kokić AN, Dušić ZO, Slavić M, Spasić MB, Blagojević D. Chloride channels mediate sodium sulphide-induced relaxation in rat uteri. Br J Pharmacol 2015; 172:3671-86. [PMID: 25857480 DOI: 10.1111/bph.13161] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 03/23/2015] [Accepted: 03/30/2015] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Hydrogen sulphide reduces uterine contractility and is of potential interest as a treatment for uterine disorders. The aim of this study was to explore the mechanism of sodium sulphide (Na2 S)-induced relaxation of rat uterus, investigate the importance of redox effects and ion channel-mediated mechanisms, and any interactions between these two mechanisms. EXPERIMENTAL APPROACH Organ bath studies were employed to assess the pharmacological effects of Na2 S in uterine strips by exposing them to Na2 S with or without Cl(-) channel blockers (DIDS, NFA, IAA-94, T16Ainh-A01, TA), raised KCl (15 and 75 mM), K(+) channel inhibitors (glibenclamide, TEA, 4-AP), L-type Ca(2+) channel activator (S-Bay K 8644), propranolol and methylene blue. The activities of antioxidant enzymes were measured in homogenates of treated uteri. The expression of bestrophin channel 1 (BEST-1) was determined by Western blotting and RT-PCR. KEY RESULTS Na2 S caused concentration-dependent reversible relaxation of spontaneously active and calcium-treated uteri, affecting both amplitude and frequency of contractions. Uteri exposed to 75 mM KCl were less sensitive to Na2 S compared with uteri in 15 mM KCl. Na2 S-induced relaxations were abolished by DIDS, but unaffected by other modulators or by the absence of extracellular HCO3 (-) , suggesting the involvement of chloride ion channels. Na2 S in combination with different modulators provoked specific changes in the anti-oxidant profiles of uteri. The expression of BEST-1, both mRNA and protein, was demonstrated in rat uteri. CONCLUSIONS AND IMPLICATIONS The relaxant effects of Na2 S in rat uteri are mediated mainly via a DIDS-sensitive Cl(-) -pathway. Components of the relaxation are redox- and Ca(2+) -dependent.
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Affiliation(s)
- Ana Mijušković
- Department of Physiology, Institute for Biological Research 'Siniša Stanković', University of Belgrade, Belgrade, Serbia
| | - Aleksandra Nikolić Kokić
- Department of Physiology, Institute for Biological Research 'Siniša Stanković', University of Belgrade, Belgrade, Serbia
| | - Zorana Oreščanin Dušić
- Department of Physiology, Institute for Biological Research 'Siniša Stanković', University of Belgrade, Belgrade, Serbia
| | - Marija Slavić
- Department of Physiology, Institute for Biological Research 'Siniša Stanković', University of Belgrade, Belgrade, Serbia
| | - Mihajlo B Spasić
- Department of Physiology, Institute for Biological Research 'Siniša Stanković', University of Belgrade, Belgrade, Serbia
| | - Duško Blagojević
- Department of Physiology, Institute for Biological Research 'Siniša Stanković', University of Belgrade, Belgrade, Serbia
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Affiliation(s)
- W. J. Lammers
- Department of Physiology; College of Medicine & Health Sciences; UAE University; Al Ain United Arab Emirates
| | - G. J. van der Vusse
- Emeritus of Physiology; Cardiovascular Research Institute Maastricht; Maastricht University; Maastricht the Netherlands
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