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Britto-Júnior J, Uramoto EHS, Lima AT, Ribeiro LF, de Souza VB, Schenka AA, de Almeida Magalhães JC, Antunes E, Fregonesi A, De Nucci G. Epithelium-derived 6-nitrodopamine modulates noradrenaline-induced contractions in human seminal vesicles. Life Sci 2024; 348:122695. [PMID: 38710285 DOI: 10.1016/j.lfs.2024.122695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/18/2024] [Accepted: 05/03/2024] [Indexed: 05/08/2024]
Abstract
AIMS To evaluate the basal release of 6-nitrodopamine (6-ND) from human isolated seminal vesicles (HISV) and to characterize its action and origin. MAIN METHODS Left HISV obtained from patients undergoing prostatectomy surgery was suspended in a 3-mL organ bath containing warmed (37 °C) and gassed (95%O2:5%CO2) Krebs-Henseleit's solution (KHS) with ascorbic acid. An aliquot of 2 mL of the supernatant was used to quantify catecholamines by LC-MS/MS. For functional studies, concentration-responses curves to catecholamines were obtained, and pEC50 and Emax values were calculated. Detection of tyrosine hydroxylase and S100 protein were also carried out by both immunohistochemistry and fluorescence in-situ hybridization assays (FISH). KEY FINDINGS Basal release of 6-ND was higher than the other catecholamines (14.76 ± 14.54, 4.99 ± 6.92, 3.72 ± 4.35 and 5.13 ± 5.76 nM for 6-ND, noradrenaline, adrenaline, and dopamine, respectively). In contrast to the other catecholamines, the basal release of 6-ND was not affected by the sodium current (Nav) channel inhibitor tetrodotoxin (1 μM; 10.4 ± 8.9 and 10.4 ± 7.9 nM, before and after tetrodotoxin, respectively). All the catecholamines produced concentration-dependent HISV contractions (pEC50 4.1 ± 0.2, 4.9 ± 0.3, 5.0 ± 0.3, and 3.9 ± 0.8 for 6-ND, noradrenaline, adrenaline, and dopamine, respectively), but 6-ND was 10-times less potent than noradrenaline and adrenaline. However, preincubation with very low concentration of 6-ND (10-8 M, 30 min) produced significant leftward shifts of the concentration-response curves to noradrenaline. Immunohistochemical and FISH assays identified tyrosine hydroxylase in tissue epithelium of HISV strips. SIGNIFICANCE Epithelium-derived 6-ND is the major catecholamine released from human isolated seminal vesicles and that modulates smooth muscle contractility by potentiating noradrenaline-induced contractions.
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Affiliation(s)
- José Britto-Júnior
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil.
| | | | - Antonio Tiago Lima
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Luiz Fernando Ribeiro
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil; Clinical Pharmacology Unit, Drug Research and Development Center, Federal University of Ceará (UFC), Fortaleza, Brazil
| | - Valéria Barbosa de Souza
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Andre Almeida Schenka
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil
| | | | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Adriano Fregonesi
- Department of Surgery, Faculty of Medicine of Jundiaí, Jundiaí, Brazil; Division of Urology, Department of Surgery, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Gilberto De Nucci
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil; Department of Surgery, Faculty of Medicine of Jundiaí, Jundiaí, Brazil; Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, Brazil
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Li S, Li Z, Yang J, Ha Y, Zhou X, He C. Inhibition of Sympathetic Activation by Delivering Calcium Channel Blockers from a 3D Printed Scaffold to Promote Bone Defect Repair. Adv Healthc Mater 2022; 11:e2200785. [PMID: 35666701 DOI: 10.1002/adhm.202200785] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/06/2022] [Indexed: 01/24/2023]
Abstract
Enhancing osteogenesis by promoting neural network reconstruction and neuropeptide release is considered to be an attractive strategy for repairing of critical size bone defects. However, traumatic bone defects often activate the damaged sympathetic nervous system (SNS) in the defect area and release excessive catecholamine to hinder bone defect repair. Herein, a 3D printed scaffold loaded with the calcium channel blocker-nifedipine is proposed to reduce the concentration of catecholamine present in the bone defect region and to accelerate bone healing. To this end, nifedipine-loaded ethosome and laponite are added into a mixed solution containing sodium alginate, methacrylated gelatin, and bone mesenchymal stem cells (BMSCs) to prepare a cell-laden scaffold using 3D bioprinting. The released nifedipine is able to close the calcium channels of nerve cells, thereby blocking sympathetic activation and ultimately inhibiting the release of catecholamine by sympathetic nerve cells, which further promotes the osteogenic differentiation and migration of BMSCs, inhibits osteoclastogenesis in vitro, and effectively improves bone regeneration in a rat critical-size calvarial defect model. Therefore, the results suggest that sustained release of nifedipine from the scaffold can effectively block SNS activation, providing promising strategies for future treatment of bone defects.
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Affiliation(s)
- Shikai Li
- Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China
| | - Zhihui Li
- Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China
| | - Jin Yang
- Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China
| | - Yujie Ha
- Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China
| | - Xiaojun Zhou
- Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China
| | - Chuanglong He
- Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China
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Mucosa-Dependent, Stretch-Sensitive Spontaneous Activity in Seminal Vesicle. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019. [PMID: 31183829 DOI: 10.1007/978-981-13-5895-1_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Seminal vesicles (SVs), a pair of male accessory glands, contract upon sympathetic nerve excitation during ejaculation while developing spontaneous phasic constrictions in the inter-ejaculatory storage phase. Recently, the fundamental role of the mucosa in generating spontaneous activity in SV of the guinea pig has been revealed. Stretching the mucosa-intact but not mucosa-denuded SV smooth muscle evokes spontaneous phasic contractions arising from action potential firing triggered by electrical slow waves and associated Ca2+ flashes. These spontaneous events primarily depend on sarco-endoplasmic reticulum (SR/ER) Ca2+ handling linked with the opening of Ca2+-activated chloride channels (CaCCs) resulting in the generation of slow waves. Slow waves in mucosa-intact SV smooth muscle are abolished upon blockade of gap junctions, suggesting that seminal smooth muscle cells are driven by cells distributed in the mucosa. In the SV mucosal preparations dissected free from the smooth muscle layer, a population of cells located just beneath the epithelium develop spontaneous Ca2+ transients relying on SR/ER Ca2+ handling. In the lamina propria of the SV mucosa, vimentin-immunoreactive interstitial cells including platelet-derived growth factor receptor α (PDGFRα)-immunoreactive cells are distributed, while known pacemaker cells in other smooth muscle tissues, e.g. c-Kit-positive interstitial cells or α-smooth muscle actin-positive atypical smooth muscle cells, are absent. The spontaneously-active subepithelial cells appear to drive spontaneous activity in SV smooth muscle either by sending depolarizing signals or by releasing humoral substances. Interstitial cells in the lamina propria may act as intermediaries of signal transmission from the subepithelial cells to the smooth muscle cells.
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Takeya M, Hashitani H, Hayashi T, Higashi R, Nakamura KI, Takano M. Role of mucosa in generating spontaneous activity in the guinea pig seminal vesicle. J Physiol 2017; 595:4803-4821. [PMID: 28421606 DOI: 10.1113/jp273872] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 04/11/2017] [Indexed: 01/08/2023] Open
Abstract
KEY POINTS The mucosa may have neuron-like functions as urinary bladder mucosa releases bioactive substances that modulate sensory nerve activity as well as detrusor muscle contractility. However, such mucosal function in other visceral organs remains to be established. The role of mucosa in generating spontaneous contractions in seminal vesicles (SVs), a paired organ in the male reproductive tract, was investigated. The intact mucosa is essential for the generation of spontaneous phasic contractions of SV smooth muscle arising from electrical slow waves and corresponding increases in intracellular Ca2+ . These spontaneous events primarily depend on Ca2+ handling by sarco-endoplasmic reticulum Ca2+ stores. A population of mucosal cells developed spontaneous rises in intracellular Ca2+ relying on sarco-endoplasmic reticulum Ca2+ handling. The spontaneously active cells in the SV mucosa appear to drive spontaneous activity in smooth muscle either by sending depolarizing signals and/or by releasing humoral substances. ABSTRACT The role of the mucosa in generating the spontaneous activity of guinea-pig seminal vesicle (SV) was explored. Changes in contractility, membrane potential and intracellular Ca2+ dynamics of SV smooth muscle cells (SMCs) were recorded using isometric tension recording, intracellular microelectrode recording and epi-fluorescence Ca2+ imaging, respectively. Mucosa-intact but not mucosa-denuded SV preparations generated TTX- (1 μm) resistant spontaneous phasic contractions that were abolished by nifedipine (3 μm). Consistently, SMCs developed mucosa-dependent slow waves (SWs) that triggered action potentials and corresponding Ca2+ flashes. Nifedipine (10 μm) abolished the action potentials and spontaneous contractions, while suppressing the SWs and Ca2+ flashes. Both the residual SWs and spontaneous Ca2+ transients were abolished by cyclopiazonic acid (CPA, 10 μm), a sarco-endoplasmic reticulum Ca2+ -ATPase (SERCA) inhibitor. DIDS (300 μm) and niflumic acid (100 μm), blockers for Ca2+ -activated Cl- channels (CACCs), or low Cl- solution also slowed or prevented the generation of SWs. In SV mucosal preparations detached from the muscle layer, a population of mucosal cells generated spontaneous Ca2+ transients that were blocked by CPA but not nifedipine. These results suggested that spontaneous contractions and corresponding Ca2+ flashes in SV SMCs arise from action potential generation due to the opening of L-type voltage-dependent Ca2+ channels. Spontaneous Ca2+ transients appear to primarily result from Ca2+ release from sarco-endoplasmic reticulum Ca2+ stores to activate CACCs to develop SWs. The mucosal cells firing spontaneous Ca2+ transients may play a critical role in driving spontaneous activity of SV smooth muscle either by sending depolarizing signals or by releasing humoral substances.
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Affiliation(s)
- Mitsue Takeya
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
| | - Hikaru Hashitani
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Tokumasa Hayashi
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Ryuhei Higashi
- Electron Microscopic Laboratory, Central Research Unit of Kurume University School of Medicine, Kurume, Japan
| | - Kei-Ichiro Nakamura
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan
| | - Makoto Takano
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
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Hayashi T, Takeya M, Nakamura KI, Matsuoka K. Effects of Silodosin and Tamsulosin on the Seminal Vesicle Contractile Response. Low Urin Tract Symptoms 2016; 8:55-61. [PMID: 26789544 DOI: 10.1111/luts.12072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 06/25/2014] [Accepted: 06/29/2014] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To understand the mechanisms underlying ejaculation dysfunction caused by α1A-adrenocetor (AR) antagonists, the effects of α1A-AR antagonists on the contractile responses of the seminal vesicle were investigated. METHODS Isolated seminal vesicles from guinea pigs were cannulated and pressurized, and the changes in the intraluminal pressure were recorded. Periodic applications of electrical stimulation (ES) caused biphasic increase in the intraluminal pressure, that is, initial and subsequent contractions. The effects of silodosin and tamsulosin, α1A-AR antagonists, on the contractile responses were examined. RESULTS The ES-induced biphasic contractions were blocked by tetrodotoxin (TTX). Silodosin and tamsulosin suppressed the initial contractions in a dose-dependent manner, while also exerting various inhibitory effects on the subsequent contractions. Increases in the intraluminal pressure facilitated spontaneous phasic contractions. The spontaneous contractions were not affected by TTX or α1A-AR antagonists, but were abolished by nifedipine. CONCLUSIONS The initial contractions triggered by neuronal excitations were suppressed by silodosin and tamsulosin, suggesting that the ejaculation dysfunction may be attributed to the α1A-AR antagonist-mediated suppression of nerve-evoked contractions in the seminal vesicle. The subsequent contractions may be induced by mechanical stimulation associated with the initial, nerve-evoked contractions. Alternatively, other transmitters may be involved to various degrees in the neuromuscular transmission of the seminal vesicle.
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Affiliation(s)
- Tokumasa Hayashi
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Mitsue Takeya
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
| | - Kei-ichiro Nakamura
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan
| | - Kei Matsuoka
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
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de Almeida Kiguti LR, Pupo AS. Investigation of the Effects of α1‐Adrenoceptor Antagonism and L‐Type Calcium Channel Blockade on Ejaculation and Vas Deferens and Seminal Vesicle Contractility In Vitro. J Sex Med 2012; 9:159-68. [DOI: 10.1111/j.1743-6109.2011.02410.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Parasympathetic Influence Plays an Independent and Significant Role in Inducing the Contraction of the Seminal Vesicle of the Rat. Urology 2010; 76:511.e1-4. [DOI: 10.1016/j.urology.2010.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 02/18/2010] [Accepted: 03/01/2010] [Indexed: 11/22/2022]
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Birowo P, Uckert S, Kedia GT, Sonnenberg JE, Thon WF, Rahardjo D, Kuczyk MA. Characterization of the effects of various drugs likely to affect smooth muscle tension on isolated human seminal vesicle tissue. Urology 2009; 75:974-8. [PMID: 19969333 DOI: 10.1016/j.urology.2009.09.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 08/03/2009] [Accepted: 09/12/2009] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To investigate the effects of different classes of drugs on the isometric tension of isolated human seminal vesicle (SV) tissue. The contractility of human SV contributes to the process of seminal emission during ejaculation. Different endogenous compounds, such as serotonin (5-HT), adenosine triphosphate (ATP), and nitric oxide, have been suggested to be involved in the control of contraction and relaxation of human SV smooth muscle. However, only limited data are available regarding the effects of compounds known to affect smooth musculature on SV contractile activity. METHODS Using the organ bath technique, the effects of increasing concentrations (10 nm-1 microm/10 microm) of norepinephrine (NE), phenylephrine, endothelin 1, ATP, and 5-HT on human SV tissue at basal tension were studied. In another set-up, SV strip preparations were preincubated with prazosin (alpha-adrenergic blocker), nifedipine and verapamil (Ca(2+)-channel blockers), 2-aminoethoxydiphenyl borate [inositol 1,4,5-trisphosphate (IP(3)) antagonist], cromakalim (K(+)-channel opener), or Y-27632 (ROK inhibitor) (1 microm each, for 10 minutes), followed by the application of NE (0.1 microM, 1 microM, and 10 microm). RESULTS SV smooth muscle was most effectively contracted by NE (mean = 75% of calibrated scale), phenylephrine (mean = 82% of calibrated scale), and endothelin 1 (mean = 70% calibrated scale), whereas only minor responses to ATP (mean = 10.65% calibrated scale) and 5-HT (mean = 6.3% calibrated scale) were observed. The contraction induced by NE was significantly inhibited after pre-exposure of the tissue to prazosin (-92.4%), cromakalim (-83.7%), 2-aminoethoxydiphenyl borate (-43.1%), Y-27632 (-42.8%), and nifedipine (-32.7%). CONCLUSIONS alpha-adrenoceptor antagonism, activation of potassium channels, and inhibition of Rho-kinase decrease the sympathetic contraction of SV smooth muscle. This might be of significance with regard to the identification of new pharmacologic avenues to affect the male ejaculatory system.
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Affiliation(s)
- Ponco Birowo
- Department of Urology, University of Indonesia School of Medicine, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
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Morrison JFB, Dhanasekaran S, Sheen R, Frampton CM, Mensah-Brown E. The effect of streptozotocin-induced diabetes on the rat seminal vesicle: A possible pathophysiological basis for disorders of ejaculation. Ann N Y Acad Sci 2007; 1084:267-79. [PMID: 17151307 DOI: 10.1196/annals.1372.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In the streptozotocin (STZ)-diabetic rat major increases in noradrenaline concentration and content of the seminal vesicles were evident as early as 7 weeks following induction of hyperglycemia and returned toward normal after 34 weeks of hyperglycemia. There were significant reductions in the concentration and content of dopamine at 19-42 weeks of diabetes, and small occasionally significant reductions in the content of serotonin and adrenaline, particularly around 19-26 weeks after STZ treatment. The uptake of tritiated noradrenaline in the diabetics was increased at 12 weeks compared to the controls, and decreased to control levels with increasing age. Release of tritiated noradrenline was increased in response to electrical field stimulation and high potassium solutions, and raising calcium concentration caused increased release at rest and during electrical stimulation. Immunohistochemical demonstration of tyrosine hydroxylase was increased during the period when the noradrenaline concentration and content were elevated. It is concluded that there are significant changes in the sympathetic innervation of the seminal vesicle during the course of STZ diabetes, and that alterations in the reuptake, release, and synthesis of the neurotransmitter noradrenaline may contribute to changes in the concentration of the amine in the tissue. It is possible that the changes observed are related to the remodeling and regrowth of sympathetic nerve endings damaged in the early stages of hyperglycemia. These changes may also contribute to disorders of ejaculation in diabetes.
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Affiliation(s)
- J F B Morrison
- Department of Physiology, Faculty of Medicine and Health Sciences, UAE University, PO Box 17666, Al Ain, United Arab Emirates.
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Orhan I, Onur R, Taşdemir C, Ayar A, Kadioğlu A. Sildenafil Citrate Inhibits Agonist Induced Contractions in Isolated Rat Seminal Vesicles. J Urol 2006; 175:2350-3. [PMID: 16697872 DOI: 10.1016/s0022-5347(06)00280-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Indexed: 11/25/2022]
Abstract
PURPOSE Sildenafil is reported to regulate smooth muscle contractility through nitric oxide-cyclic guanosine monophosphate, not only in the corpus cavernosum. Its possible effects on seminal vesicle contractility might be of importance with respect to premature ejaculation. We investigated the effects of sildenafil citrate (Pfizer, New York, New York) on agonist induced isometric contractions of the rat seminal vesicle in vitro. MATERIALS AND METHODS Seminal vesicles isolated from adult male Wistar rats were suspended in an organ bath and contracted by NE (10 microM), ACh (10 microM) or KCl (60 mM) (Sigma, Deisenhofen, Germany). The effects of sildenafil citrate (100 to 300 microM) were evaluated in terms of mean contraction amplitude, the area under force-time curves and isometric contractility indexes. RESULTS Sildenafil citrate (300 microM) significantly inhibited the mean amplitude +/- SEM of contractile responses induced by NE (1,061 +/- 153 vs 271 +/- 65 mg, p <0.0001), ACh (475 +/- 51 vs 68 +/- 17 mg, p <0.0001) and KCl (546 +/- 71 vs 59 +/- 18 mg, p <0.0002). It also caused dose dependent concomitant decreases in the area under force-time curves. Additionally, pretreatment with sildenafil citrate markedly prevented the contractile response to NE, ACh and KCl. CONCLUSIONS Our results indicate that sildenafil citrate inhibits the contractions of isolated rat seminal vesicle that are induced by NE, ACh or KCl. Future studies may support an in vivo effect of sildenafil for delaying or inhibiting seminal vesicle emission, thereby, promoting improvement in patients with premature ejaculation.
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Affiliation(s)
- Irfan Orhan
- Department of Urology, Firat University, Elazig, Istanbul, Turkey
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Abdel-Hamid IA. Can smooth muscle represent a useful target for the treatment of rapid ejaculation? Drug Discov Today 2005; 10:1459-66. [PMID: 16243266 DOI: 10.1016/s1359-6446(05)03596-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Rapid ejaculation is probably the most common form of male sexual dysfunction. Current research into the treatment of the condition has focused on centrally acting or topical desensitizing agents; however, no treatment has yet been approved. An alternative approach could be to develop drugs that act directly upon the target organ itself and our increasing knowledge of the molecular biology of the accessory sex organs makes this a realistic possibility. This review analyzes the information in the literature that would support such a hypothesis. Particular emphasis has been placed on articles that have investigated smooth muscle cell relaxation. A critical review of the literature has revealed that there are potentially a myriad of targets through which rapid ejaculation can be treated.
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Burnstock G, Knight GE. Cellular Distribution and Functions of P2 Receptor Subtypes in Different Systems. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 240:31-304. [PMID: 15548415 DOI: 10.1016/s0074-7696(04)40002-3] [Citation(s) in RCA: 581] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review is aimed at providing readers with a comprehensive reference article about the distribution and function of P2 receptors in all the organs, tissues, and cells in the body. Each section provides an account of the early history of purinergic signaling in the organ?cell up to 1994, then summarizes subsequent evidence for the presence of P2X and P2Y receptor subtype mRNA and proteins as well as functional data, all fully referenced. A section is included describing the plasticity of expression of P2 receptors during development and aging as well as in various pathophysiological conditions. Finally, there is some discussion of possible future developments in the purinergic signaling field.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Institute, Royal Free and University College Medical School, London NW3 2PF, United Kingdom
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Barber NJ, Muir GH. High-power KTP laser prostatectomy: the new challenge to transurethral resection of the prostate. Curr Opin Urol 2004; 14:21-5. [PMID: 15091045 DOI: 10.1097/00042307-200401000-00005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE OF REVIEW The quest for a successful surgical modality that can be used in the day-case setting, with minimal risk of complications and without the need for postoperative catheter drainage, may finally be fulfilled in the form of the new-generation, high-power potassium titanyl phosphate (KTP) lasers. In this review we will trace the development of KTP laser technology and its use by urologists over the years and describe why its physical properties make it so different from the lasers of the past. RECENT FINDINGS The most high powered (80 W) incarnation has a relatively short history, particularly in terms of peer-reviewed publications. We will, however, outline the data so far and demonstrate what an exciting tool this represents for the urologist not only in terms of qualitative and quantitative improvements in lower urinary tract symptoms, but also in offering a day case, and in some instances catheterless, procedure with the prospect of a significantly lower impact on sexual function compared with standard surgical options. SUMMARY Despite the lack of long-term data it is certainly possible that high-power KTP lasers represent a very significant challenge to the 'gold standard' status of transurethral resection of the prostate. Furthermore, the ability to use this technology to safely and effectively treat very large prostates represents an opportunity to assign the associated morbidity of the open prostatectomy to the annals of history.
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Affiliation(s)
- Neil J Barber
- Department of Urology, King's College Hospital, London, UK
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