1
|
Miller VM, Disharoon M, Padilla LA, Beierle EA, Dabal RJ. A Multidisciplinary Surgical Approach to Mediastinal Masses in Children. World J Pediatr Congenit Heart Surg 2023; 14:180-184. [PMID: 36803216 DOI: 10.1177/21501351221133753] [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] [Indexed: 02/22/2023]
Abstract
The aim of this study is to demonstrate the safety and advantages of a multidisciplinary approach to surgical resection of mediastinal masses in children. Eight patients underwent resection of a mediastinal mass by a team involving both a pediatric general surgeon and pediatric cardiothoracic surgeon. One patient required rapid initiation of cardiopulmonary bypass to complete the tumor resection and repair an aortic injury that occurred when removing adherent tumor from the structure. Perioperative outcomes were excellent for all patients. This series shows that a multidisciplinary surgical approach can be potentially life saving.
Collapse
Affiliation(s)
- Vanessa M Miller
- Division of Cardiothoracic Surgery, Department of Surgery, 22078University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mitchell Disharoon
- Division of Cardiothoracic Surgery, Department of Surgery, 22078University of Alabama at Birmingham, Birmingham, AL, USA
| | - Luz A Padilla
- Division of Cardiothoracic Surgery, Department of Surgery, 22078University of Alabama at Birmingham, Birmingham, AL, USA
| | - Elizabeth A Beierle
- Division of Pediatric Surgery, Department of Surgery, 22078University of Alabama at Birmingham, Birmingham, AL, USA
| | - Robert J Dabal
- Division of Cardiothoracic Surgery, Department of Surgery, 22078University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
2
|
Miller VM, Sorabella RA, Padilla LA, Sollie Z, Izima C, Johnson WH, Cleveland DC, Buckman JR, Maxwell KS, Smith R, Dabal RJ. Health-Related Quality of Life After Single Ventricle Palliation or Tetralogy of Fallot Repair. Pediatr Cardiol 2023; 44:95-101. [PMID: 35841405 DOI: 10.1007/s00246-022-02958-1] [Citation(s) in RCA: 1] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 06/11/2022] [Indexed: 01/24/2023]
Abstract
Single ventricle (SV) cardiac lesions and tetralogy of Fallot (TOF) are both common forms of cyanotic congenital heart disease. With advances in perioperative care and longitudinal follow-up, survival of these patients has dramatically improved and the majority survive to adulthood. This study compares health-related quality of life (HRQoL) of adult SV and TOF patients to each other and the general population. HRQoL of all surviving, non-transplanted SV and TOF patients 21 years of age and older at our institution was assessed with the SF-36 questionnaire via phone. Additional data including demographic parameters and information related to comorbidities and healthcare utilization were also analyzed. Among 81 eligible SV patients and 207 TOF patients, 33 (41%) and 75 (36%) completed the SF-36 phone survey, respectively. The mean age of SV patients was 32 vs. 38 years in the TOF group (p=0.01). SV patients reported more hepatic, pulmonary, and renal comorbidities. TOF patients were more likely to complete advanced degrees and more likely to have children (p=0.03). SV physical functioning scores were worse compared to TOF. In other domains of the SF-36 questionnaire, SV and TOF scores were similar. Compared to the general population, both groups reported worse bodily pain and mental health, but other aspects of psychosocial and general health were comparable. Overall HRQoL is good for both SV and TOF patients through early and mid-adulthood. Some QoL metrics were modestly worse in the SV patients. While these patients may have some physical limitations, psychosocial wellbeing appears preserved.
Collapse
Affiliation(s)
- Vanessa M Miller
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA
| | - Robert A Sorabella
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA
| | - Luz A Padilla
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA
| | - Zachary Sollie
- Division of Cardiothoracic Surgery, Department of Surgery, Medical University of South Carolina, Charleston, SC, USA
| | - Chiemela Izima
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA
| | - Walter H Johnson
- Department of Pediatric Cardiology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA
| | - David C Cleveland
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA
| | - Joseph R Buckman
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA
| | - Kathryn S Maxwell
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA
| | - Royal Smith
- Department of Pediatric Cardiology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA
| | - Robert J Dabal
- Division of Cardiothoracic Surgery, Department of Surgery, University of Alabama at Birmingham School of Medicine, 1700 6th Avenue South, WIC 9100, Birmingham, AL, 35249, USA.
| |
Collapse
|
3
|
Miller VM, Taylor HS, Naftolin F, Manson JE, Gleason CE, Brinton EA, Kling JM, Cedars MI, Dowling NM, Kantarci K, Harman SM. Lessons from KEEPS: the Kronos Early Estrogen Prevention Study. Climacteric 2020; 24:139-145. [PMID: 32880220 DOI: 10.1080/13697137.2020.1804545] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 12/11/2022]
Abstract
The Kronos Early Estrogen Prevention Study (KEEPS) was a randomized, double-blind, placebo-controlled trial designed to determine the effects of hormone treatments (menopausal hormone treatments [MHTs]) on the progression of carotid intima-medial thickness (CIMT) in recently menopausal women. Participants less than 3 years from menopause and without a history of overt cardiovascular disease (CVD), defined as no clinical CVD events and coronary artery calcium < 50 Agatston units, received either oral conjugated equine estrogens (0.45 mg/day) or transdermal 17β-estradiol (50 µg/day), both with progesterone (200 mg/day for 12 days/month), or placebo pills and patches for 4 years. Although MHT did not decrease the age-related increase in CIMT, KEEPS provided other important insights about MHT effects. Both MHTs versus placebo reduced the severity of menopausal symptoms and maintained bone density, but differed in efficacy regarding mood/anxiety, sleep, sexual function, and deposition of β-amyloid in the brain. Additionally, genetic variants in enzymes for metabolism and uptake of estrogen affected the efficacy of MHT for some aspects of symptom relief. KEEPS provides important information for use of MHT in clinical practice, including type, dose, and mode of delivery of MHT recently after menopause, and how genetic variants in hormone metabolism may affect MHT efficacy on specific outcomes.
Collapse
Affiliation(s)
- V M Miller
- Department of Surgery, Mayo Clinic College of Medicine, Rochester, MN, USA.,Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - H S Taylor
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT, USA
| | - F Naftolin
- Department of Obstetrics and Gynecology, New York University Grossman School of Medicine, New York, NY, USA
| | - J E Manson
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - C E Gleason
- Division of Geriatrics, Department of Medicine, Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | - J M Kling
- Department of Internal Medicine, Division of Women's Health Internal Medicine, Mayo Clinic, AZ, USA
| | - M I Cedars
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - N M Dowling
- Department of Acute & Chronic Care, School of Nursing, Department of Epidemiology & Biostatistics, Milken Institute School of Public Health, The George Washington University, Washington DC, USA
| | - K Kantarci
- Department of Radiology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - S M Harman
- Kronos Longevity Research Institute, Phoenix, AZ, USA.,Phoenix Veterans Administration Health Care System, Phoenix, AZ, USA
| |
Collapse
|
4
|
Miller VM, Pereira SJ. Authors' response to letter to the editor: "Therapeutic strategy of dialysis catheter-associated massive thrombus". J Card Surg 2020; 35:2115. [PMID: 32652715 DOI: 10.1111/jocs.14727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Vanessa M Miller
- Division of Cardiovascular Surgery, Department of Surgery, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Sara J Pereira
- Division of Cardiovascular Surgery, Department of Surgery, The University of Alabama at Birmingham, Birmingham, Alabama
| |
Collapse
|
5
|
Miller VM, Pereira SJ. Surgical management of catheter-related right atrial thrombus with superior vena cava syndrome A Case Report. J Card Surg 2020; 35:1673-1675. [PMID: 32365429 DOI: 10.1111/jocs.14613] [Citation(s) in RCA: 1] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 04/27/2020] [Indexed: 11/29/2022]
Abstract
There are no consensus guidelines on the management of catheter-related right atrial thrombus. We present the case of a 29-year-old female with end-stage renal disease who was found to have a large right atrial thrombus associated with her tunneled dialysis catheter during preoperative workup for renal transplant. She exhibited signs and symptoms of superior vena cava syndrome and NYHA class III congestive heart failure. She was successfully treated with surgical thrombectomy and demonstrated rapid resolution of her symptoms postoperatively.
Collapse
Affiliation(s)
- Vanessa M Miller
- Division of Cardiovascular Surgery, Department of Surgery, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Sara J Pereira
- Division of Cardiovascular Surgery, Department of Surgery, The University of Alabama at Birmingham, Birmingham, Alabama
| |
Collapse
|
6
|
Affiliation(s)
- Vanessa M. Miller
- Department of Cardiovascular SurgeryThe University of Alabama at BirminghamBirmingham Alabama
| | - Panos N. Vardas
- Department of Cardiovascular SurgeryThe University of Alabama at BirminghamBirmingham Alabama
| | - James E. Davies
- Department of Cardiovascular SurgeryThe University of Alabama at BirminghamBirmingham Alabama
| | - Clifton T. Lewis
- Department of Cardiovascular SurgeryThe University of Alabama at BirminghamBirmingham Alabama
| |
Collapse
|
7
|
Miller VM, Padilla LA, Schuh A, Mauchley D, Cleveland D, Aburjania Z, Dabal R. Evaluation of Cardiothoracic Surgery Residency and Fellowship Program Websites. J Surg Res 2020; 246:200-206. [DOI: 10.1016/j.jss.2019.09.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 07/19/2019] [Accepted: 09/12/2019] [Indexed: 10/25/2022]
|
8
|
Barnes JN, Harvey RE, Eisenmann NA, Miller KB, Johnson MC, Kruse SM, Lahr BD, Joyner MJ, Miller VM. Cerebrovascular reactivity after cessation of menopausal hormone treatment. Climacteric 2019; 22:182-189. [PMID: 30661405 DOI: 10.1080/13697137.2018.1538340] [Citation(s) in RCA: 2] [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] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Women who are currently using menopausal hormone therapy (MHT) have higher cerebrovascular reactivity when compared with postmenopausal women who are not taking MHT; however, the effect of cessation of MHT on cerebrovascular reactivity is not known. Given that MHT can have structural and activational effects on vascular function, this study was performed to characterize cerebrovascular reactivity following cessation of MHT in women at low risk for cerebrovascular disease. METHODS Cerebrovascular reactivity was measured in a subset of women from the Kronos Early Estrogen Prevention Study (KEEPS) 3 years after cessation of the study drug (oral conjugated equine estrogen, transdermal 17β-estradiol, or placebo [PLA]). RESULTS Age, body mass index, and blood pressure were comparable among groups. At rest, the middle cerebral artery velocity (MCAv), cerebrovascular conductance index, mean arterial pressure, and cerebral pulsatility index did not differ among groups. Slope-based summary measures of cerebrovascular reactivity did not differ significantly among groups. However, utilizing repeated-measures modeling, there was a significant upward shift in MCAv responses (p = 0.029) in the combined MHT group compared with the PLA group. CONCLUSION MHT has a marginal sustained effect on cerebrovascular reactivity when measured 3 years after cessation of hormone treatment.
Collapse
Affiliation(s)
- J N Barnes
- a Department of Kinesiology , University of Wisconsin-Madison , Madison , WI , USA.,b Department of Anesthesiology , Mayo Clinic , Rochester , MN , USA
| | - R E Harvey
- b Department of Anesthesiology , Mayo Clinic , Rochester , MN , USA.,c College of Medicine and Science , Mayo Clinic , Rochester , MN , USA
| | - N A Eisenmann
- a Department of Kinesiology , University of Wisconsin-Madison , Madison , WI , USA
| | - K B Miller
- a Department of Kinesiology , University of Wisconsin-Madison , Madison , WI , USA
| | - M C Johnson
- b Department of Anesthesiology , Mayo Clinic , Rochester , MN , USA
| | - S M Kruse
- b Department of Anesthesiology , Mayo Clinic , Rochester , MN , USA
| | - B D Lahr
- d Department of Health Science Research , Mayo Clinic , Rochester , MN , USA
| | - M J Joyner
- b Department of Anesthesiology , Mayo Clinic , Rochester , MN , USA
| | - V M Miller
- e Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , MN , USA.,f Department of Surgery , Mayo Clinic , Rochester , MN , USA
| |
Collapse
|
9
|
Pena Orbea C, Lloyd RM, Kapoor E, Miller VM, Mara K, Faubion S. 0504 Predictive Ability And Reliability Of The Stop-Bang Questionnaire In Screening For Obstructive Sleep Apnea In Midlife Women. Sleep 2018. [DOI: 10.1093/sleep/zsy061.503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | | | | | | | - K Mara
- Mayo Clinic, Rochester, MN
| | | |
Collapse
|
10
|
Beckman JP, Camp JJ, Lahr BD, Bailey KR, Kearns AE, Garovic VD, Jayachandran M, Miller VM, Holmes DR. Pregnancy history, coronary artery calcification and bone mineral density in menopausal women. Climacteric 2017; 21:53-59. [PMID: 29189095 DOI: 10.1080/13697137.2017.1406910] [Citation(s) in RCA: 9] [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: 12/16/2022]
Abstract
OBJECTIVE This study examined relationships, by pregnancy histories, between bone mineral density (BMD) and coronary artery calcification (CAC) in postmenopausal women. METHODS Forty women identified from their medical record as having pre-eclampsia (PE) were age/parity-matched with 40 women having a normotensive pregnancy (NP). Vertebral (T4-9) BMD and CAC were assessed by quantitative computed tomography in 73 (37 with PE and 36 with NP) of the 80 women. Analyses included linear regression using generalized estimating equations. RESULTS Women averaged 59 years of age and 35 years from the index pregnancy. There were no significant differences in cortical, trabecular or central BMD between groups. CAC was significantly greater in the PE group (p = 0.026). In multivariable analysis, CAC was positively associated with cortical BMD (p = 0.001) and negatively associated with central BMD (p = 0.036). There was a borderline difference in the association between CAC and central BMD by pregnancy history (interaction, p = 0.057). CONCLUSIONS Although CAC was greater in women with a history of PE, vertebral BMD did not differ between groups. However, both cortical and central BMD were associated with CAC. The central BMD association was marginally different by pregnancy history, suggesting perhaps differences in underlying mechanisms of soft tissue calcification.
Collapse
Affiliation(s)
- J P Beckman
- a Department of Surgery , Mayo Clinic , Rochester , MN , USA
| | - J J Camp
- b Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , MN , USA
| | - B D Lahr
- c Department of Health Science Research, Division of Biostatistics , Mayo Clinic , Rochester , MN , USA
| | - K R Bailey
- c Department of Health Science Research, Division of Biostatistics , Mayo Clinic , Rochester , MN , USA
| | - A E Kearns
- d Department of General Internal Medicine, Division of Endocrinology , Mayo Clinic , Rochester , MN , USA
| | - V D Garovic
- e Department of General Internal Medicine, Division of Nephrology and Hypertension , Mayo Clinic , Rochester , MN , USA
| | - M Jayachandran
- a Department of Surgery , Mayo Clinic , Rochester , MN , USA.,b Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , MN , USA
| | - V M Miller
- a Department of Surgery , Mayo Clinic , Rochester , MN , USA.,b Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , MN , USA
| | - D R Holmes
- b Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , MN , USA
| |
Collapse
|
11
|
Raz L, Hunter LV, Dowling NM, Wharton W, Gleason CE, Jayachandran M, Anderson L, Asthana S, Miller VM. Differential effects of hormone therapy on serotonin, vascular function and mood in the KEEPS. Climacteric 2015; 19:49-59. [PMID: 26652904 DOI: 10.3109/13697137.2015.1116504] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND Serotonin (5-hydroxytryptamine, 5-HT) is modulated by sex steroid hormones and affects vascular function and mood. In the Kronos Early Estrogen Prevention Cognitive and Affective Ancillary Study (KEEPS-Cog), women randomized to oral conjugated equine estrogens (oCEE) showed greater benefit on affective mood states than women randomized to transdermal 17β-estradiol (tE2) or placebo (PL). This study examined the effect of these treatments on the platelet content of 5-HT as a surrogate measure of 5-HT synthesis and uptake in the brain. METHODS The following were measured in a subset (n = 79) of women enrolled in KEEPS-Cog: 5-HT by ELISA, carotid intima-medial thickness (CIMT) by ultrasound, endothelial function by reactive hyperemic index (RHI), and self-reported symptoms of affective mood states by the Profile of Mood States (POMS) questionnaire. RESULTS Mean platelet content of 5-HT increased by 107.0%, 84.5% and 39.8%, in tE2, oCEE and PL groups, respectively. Platelet 5-HT positively correlated with estrone in the oCEE group and with 17β- estradiol in the tE2 group. Platelet 5-HT showed a positive association with RHI, but not CIMT, in the PL and oCEE groups. Reduction in mood scores for depression-dejection and anger-hostility was associated with elevations in platelet 5-HT only in the oCEE group (r = -0.5, p = 0.02). CONCLUSIONS Effects of oCEE compared to tE2 on RHI and mood may be related to mechanisms involving platelet, and perhaps neuronal, uptake and release of 5-HT and reflect conversion of estrone to bioavailable 17β-estradiol in platelets and the brain.
Collapse
Affiliation(s)
- L Raz
- a Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , Minnesota , USA
| | - L V Hunter
- a Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , Minnesota , USA
| | - N M Dowling
- b Department of Biostatistics and Medical Informatics , University of Wisconsin , Madison , WI , USA ;,c Department of Medicine , University of Wisconsin and Geriatric Research, Education and Clinical Center, Madison VA Hospital , Madison , WI , USA
| | - W Wharton
- d Department of Neurology , Emory University , Atlanta , GA , USA
| | - C E Gleason
- c Department of Medicine , University of Wisconsin and Geriatric Research, Education and Clinical Center, Madison VA Hospital , Madison , WI , USA
| | - M Jayachandran
- a Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , Minnesota , USA
| | - L Anderson
- a Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , Minnesota , USA
| | - S Asthana
- c Department of Medicine , University of Wisconsin and Geriatric Research, Education and Clinical Center, Madison VA Hospital , Madison , WI , USA
| | - V M Miller
- a Department of Physiology and Biomedical Engineering , Mayo Clinic , Rochester , Minnesota , USA ;,e Department of Surgery , Mayo Clinic , Rochester , Minnesota , USA
| |
Collapse
|
12
|
Miller VM, Zhu Y, Bucher C, McGinnis W, Ryan LK, Siegel A, Zalcman S. Gestational flu exposure induces changes in neurochemicals, affiliative hormones and brainstem inflammation, in addition to autism-like behaviors in mice. Brain Behav Immun 2013; 33:153-63. [PMID: 23880236 DOI: 10.1016/j.bbi.2013.07.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 06/27/2013] [Accepted: 07/09/2013] [Indexed: 12/23/2022] Open
Abstract
The prevalence of neurodevelopmental disorders such as autism is increasing, however the etiology of these disorders is unclear and thought to involve a combination of genetic, environmental and immune factors. A recent epidemiological study found that gestational viral exposure during the first trimester increases risk of autism in offspring by twofold. In mice gestational viral exposures alter behavior of offspring, but the biological mechanisms which underpin these behavioral changes are unclear. We hypothesized that gestational viral exposure induces changes in affiliative hormones, brainstem autonomic nuclei and neurotransmitters which are associated with behavioral alterations in offspring. To address this hypothesis, we exposed pregnant mice to influenza A virus (H3N2) on gestational day 9 and determined behavioral, hormonal and brainstem changes in male and female offspring. We found that gestational flu exposure induced dose-dependent alterations in social and aggressive behaviors (p≤0.05) in male and female offspring and increases in locomotor behaviors particularly in male offspring (p≤0.05). We found that flu exposure was also associated with reductions in oxytocin and serotonin (p≤0.05) levels in male and female offspring and sex-specific changes in dopamine metabolism. In addition we found changes in catecholaminergic and microglia density in brainstem tissues of male flu exposed offspring only (p≤0.05). This study demonstrates that gestational viral exposure induces behavioral changes in mice, which are associated with alterations in affiliative hormones. In addition we found sex-specific changes in locomotor behavior, which may be associated with sex-specific alterations in dopamine metabolism and brainstem inflammation. Further investigations into maternal immune responses are necessary to unravel the molecular mechanisms which underpin abnormal hormonal, immune and behavioral responses in offspring after gestational viral exposure.
Collapse
Affiliation(s)
- V M Miller
- Clinical Medical Sciences Building, Wadsworth Center, New York State Department of Health, New Scotland Avenue, Albany, NY 12208, USA; Department of Environmental Health Science, School of Public Health, State University of New York at Albany, Wadsworth Center, Empire State Plaza, NY 12201-0509, USA.
| | | | | | | | | | | | | |
Collapse
|
13
|
Miller VM, Gupta D, Neu N, Cotroneo A, Boulay CB, Seegal RF. Novel inter-hemispheric white matter connectivity in the BTBR mouse model of autism. Brain Res 2013; 1513:26-33. [PMID: 23570707 DOI: 10.1016/j.brainres.2013.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 03/29/2013] [Accepted: 04/01/2013] [Indexed: 01/23/2023]
Abstract
Alterations in the volume, density, connectivity and functional activation of white matter tracts are reported in some individuals with autism and may contribute to their abnormal behaviors. The BTBR (BTBR T+tf/J) inbred strain of mouse, is used to model facets of autism because they develop low social behaviors, stereotypical and immune changes similar to those found in people with autism. Previously, it was thought a total absence of corpus callosal interhemispheric connective tissues in the BTBR mice may underlie their abnormal behaviors. However, postnatal lesions of the corpus callosum do not precipitate social behavioral problems in other strains of mice suggesting a flaw in this theory. In this study we used digital pathological methods to compare subcortical white matter connective tracts in the BTBR strain of mice with those found in the C57Bl/6 mouse and those reported in a standardized mouse brain atlas. We report, for the first time, a novel connective subcortical interhemispheric bridge of tissue in the posterior, but not anterior, cerebrum of the BTBR mouse. These novel connective tissues are comprised of myelinated fibers, with reduced myelin basic protein levels (MBP) compared to levels in the C57Bl/6 mouse. We used electrophysiological analysis and found increased inter-hemispheric connectivity in the posterior hemispheres of the BTBR strain compared with the anterior hemispheres. The conduction velocity was slower than that reported in normal mice. This study shows there is novel abnormal interhemispheric connectivity in the BTBR strain of mice, which may contribute to their behavioral abnormalities.
Collapse
Affiliation(s)
- V M Miller
- Wadsworth Center for Laboratories and Research, New York State Department of Health, Empire State Plaza, Albany, NY 12201-0509, USA.
| | | | | | | | | | | |
Collapse
|
14
|
Miyabara Y, Holmes D, Camp J, Miller VM, Kearns AE. Comparison of calibrated and uncalibrated bone mineral density by CT to DEXA in menopausal women. Climacteric 2011; 15:374-81. [PMID: 22175297 DOI: 10.3109/13697137.2011.618566] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES Coronary artery disease and osteoporosis increase in women after menopause. Computed tomography (CT) scans of the heart used to evaluate coronary arterial calcification include images of the thoracic vertebrae. The utility of using these images to assess bone health in women remains to be defined. Analyses of thoracic spine volumetric bone mineral density (vBMD) from CT scans of the heart were performed to determine how specific calibration affects the ability to assess vBMD in recently menopausal women and to evaluate how vBMD relates to areal bone mineral density (aBMD) using dual-energy X-ray absorptiometry (DEXA). METHODS Women (n = 111) enrolled in the Kronos Early Estrogen Prevention Study (KEEPS) at Mayo Clinic underwent a CT scan of the heart that included calibration phantoms and a DEXA of the lumbar spine. The Spine Cancer Assessment program was used to determine vBMD of thoracic vertebrae with and without the calibration correction. RESULTS Trabecular bone vBMD at T8 averaged 163.57±28.58 and 157.94±27.55 mg/cc (mean±standard deviation, SD) for calibrated and uncalibrated values, respectively. The relationship between calibrated and uncalibrated measures approached unity (R = 0.98). Lumbar spine (L2-4) aBMD was 1.19±0.16 g/cm(2) (mean±SD). Both calibrated and uncalibrated thoracic vBMD correlated positively and significantly with lumbar aBMD, but the relationship was less than unity (R = 0.63). CONCLUSION Uncalibrated measures of thoracic spine vBMD obtained from CT scans of the heart may provide clinically relevant information about bone health and osteoporosis/osteopenia risk in recently menopausal women.
Collapse
Affiliation(s)
- Y Miyabara
- Department of Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | | | | | | | | |
Collapse
|
15
|
Miyabara Y, Camp J, Holmes D, Lahr B, Bailey K, Miller VM, Kearns AE. Coronary arterial calcification and thoracic spine mineral density in early menopause. Climacteric 2011; 14:438-44. [PMID: 21265610 DOI: 10.3109/13697137.2010.537409] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVES Cardiovascular disease and osteoporosis increase in women after menopause. While aortic calcification is associated with bone loss in women, a similar relationship for coronary arterial calcification (CAC), a risk factor for coronary artery disease in women, is less clear. This study was designed to examine the relationship between CAC and volumetric bone mineral density (vBMD) in women (n=137) who were within a median of 18 months past their last menses at screening for the Kronos Early Estrogen Prevention Study (KEEPS). METHODS CAC was measured using 64-slice computed tomography; vBMD was measured from these images using the Spine Cancer Assessment program. Concentrations of osteocalcin, bone alkaline phosphatase, tartrate-resident acid phosphatase-5b and osteopontin as bone matrix protein in serum and plasma were evaluated by ELISA. RESULTS CAC scores ranged from 0 to 327.6 Agatston Units (AU); 113 women had a score of 0 AU, 20 had a CAC score between 0 and 50 AU, and four had a CAC score>50 AU. Although not statistically significant, there was a trend toward decreasing central density of thoracic T9 with increasing CAC. On average, levels of markers of bone turnover were within the normal range but did not correlate with age or with months past menopause. CONCLUSIONS Clinically significant CAC and spine vBMD are quantifiable from the same scans within the first 3 years of menopause. Additional work is needed to determine how these measurements change with increasing age or with estrogenic treatments.
Collapse
Affiliation(s)
- Y Miyabara
- Department of Surgery, Mayo Clinic, 200 First St SW. Rochester, MN 55905, USA
| | | | | | | | | | | | | |
Collapse
|
16
|
Abstract
Cardiovascular disease is the leading cause of morbidity and mortality for both men and women in the USA. However, there are differences between the sexes in age-dependent onset, severity, symptoms and outcomes. Basic research into the causes of sex-dependent differences in cardiovascular disease is ongoing and includes investigation into genetic variation in expression and distribution of receptors for the sex steroids; specificity of natural and synthetic ligands that activate the sex steroid receptors; and intracellular mechanisms that are activated by the receptors in all components of the vessel wall and blood elements, which integrate to regulate vascular tone, vascular repair and remodeling in health and disease. In this era of personalized medicine, basic research into mechanisms of sex differences in vascular function will result in improved prevention, detection and treatment of cardiovascular disease in both men and women.
Collapse
Affiliation(s)
- V M Miller
- Departments of Surgery & Physiology & Biomedical Engineering, College of Medicine, Mayo Clinic, Rochester, MN 55905, USA.
| |
Collapse
|
17
|
Mulvagh SL, Behrenbeck T, Lahr BA, Bailey KR, Zais TG, Araoz PA, Miller VM. Endothelial function and cardiovascular risk stratification in menopausal women. Climacteric 2010; 13:45-54. [PMID: 19657788 DOI: 10.3109/13697130902943287] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Peripheral arterial, endothelium-dependent, flow-mediated reactive hyperemia is reduced in individuals with atherosclerosis. This study tested the hypothesis that digital tonometry, as a surrogate of endothelial function, is useful to stratify cardiovascular risk in recently menopausal women who are asymptomatic for cardiovascular disease. METHODS Women undergoing screening for the Kronos Early Estrogen Prevention Study (KEEPS) were evaluated for conventional risk factors, flow-mediated reactive hyperemia by digital tonometry (RHI), carotid intima-media thickness (CIMT) by ultrasound, and coronary arterial calcium (CAC) by 64-slice CT scanner. RESULTS One hundred and two non-diabetic Caucasian women (53.0 +/- 2.3 years old, 18.0 +/- 9.0 months past their last menses) participated; 72% were never-smokers. Fourteen women had positive CAC scores (range 0.5-133 Agatston units); CIMT ranged from 0.57 to 1.06 mm. RHI ranged from 1.26 to 5.44. RHI did not correlate with time past menopause, CAC, CIMT, total cholesterol or low density lipoprotein cholesterol. The significant negative correlation of RHI with body mass index (r = -0.21, p = 0.031) was lost in non-smokers (r = - 0.17, p = 0.14). There was also a negative correlation of high density lipoprotein cholesterol with CAC, both in the overall group and non-smokers (rho = -0.20, p = 0.05 and rho = -0.27, p = 0.02, respectively). CONCLUSIONS RHI varies widely in healthy women within the first 3 years of menopause. RHI was not associated with standard risk assessment algorithms, CAC or CIMT. RHI may indicate an additional, independent component and non-invasive tool to further stratify cardiovascular risk in recently menopausal women. As KEEPS continues, data on RHI will provide information regarding hormonal therapy, endovascular biology and atherosclerotic risk.
Collapse
Affiliation(s)
- S L Mulvagh
- Department of Internal Medicine, Division of Cardiovascular Diseases, College of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | | | | | | | | | | | | |
Collapse
|
18
|
Miller VM, Lawrence DA, Coccaro GA, Mondal TK, Andrews K, Dreiem A, Seegal RF. Sex effects of interleukin-6 deficiency on neuroinflammation in aged C57Bl/6 mice. Brain Res 2010; 1318:11-22. [PMID: 20060814 DOI: 10.1016/j.brainres.2009.12.091] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 12/14/2009] [Accepted: 12/30/2009] [Indexed: 11/30/2022]
Abstract
High levels of Interleukin-6 (IL-6) are associated with an increased risk of dementia in the elderly and can increase neuroinflammation in mice. Dementia is more frequent in females, and IL-6 is regulated by estrogen, suggesting that elevated IL-6 levels may contribute to neuroinflammation and dementia particularly in women. Therefore we hypothesized that IL-6 deficient ((-/-)) female mice would have lower aging-related neuroinflammation than wild type (WT). We quantified neuroinflammatory markers which are affected by aging, and regulated by both estrogen and IL-6; glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), interferon gamma (IFNgamma), lipid peroxidation (MDA), and synaptic density (SNAP25) and in IL-6(-/-) and WT C57Bl/6 mice. To determine age effects we used mid-age (18months) and old-age (24months) mice, and to determine region specific effects we used the hippocampus which is impaired in dementia and the cerebellum which is unimpaired in dementia. Unexpectedly, there were no effects of IL-6 deficiency on GFAP, MDA or SNAP25 levels in females, but IL-6 deficiency was associated with lower cerebellar MBP (p<0.05) levels. Interestingly, the old-aged IL-6(-/-) males had higher GFAP and MDA levels (p<0.05) in both the hippocampus and cerebellum, in addition to a greater body weight than WT. We suggest that IL-6 is important for promoting myelin synthesis in aged females, and that drugs which inhibit the synthesis of IL-6 in males may inadvertently affect fatty acid metabolism and augment aging-related neuroinflammation.
Collapse
Affiliation(s)
- V M Miller
- Biggs Laboratory, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201, USA.
| | | | | | | | | | | | | |
Collapse
|
19
|
Miller VM, Black DM, Brinton EA, Budoff MJ, Cedars MI, Hodis HN, Lobo RA, Manson JE, Merriam GR, Naftolin F, Santoro N, Taylor HS, Harman SM. Using basic science to design a clinical trial: baseline characteristics of women enrolled in the Kronos Early Estrogen Prevention Study (KEEPS). J Cardiovasc Transl Res 2009; 2:228-39. [PMID: 19668346 PMCID: PMC2721728 DOI: 10.1007/s12265-009-9104-y] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Accepted: 04/27/2009] [Indexed: 12/24/2022]
Abstract
Observational and epidemiological studies suggest that menopausal hormone therapy (MHT) reduces cardiovascular disease (CVD) risk. However, results from prospective trials showed neutral or adverse effects most likely due to differences in participant demographics, such as age, timing of initiation of treatment, and preexisting cardiovascular disease, which reflected in part the lack of basic science information on mechanisms of action of hormones on the vasculature at the time clinical trials were designed. The Kronos Early Estrogen Replacement Study (KEEPS) is a prospective, randomized, controlled trial designed, using findings from basic science studies, to test the hypothesis that MHT when initiated early in menopause reduces progression of atherosclerosis. KEEPS participants are younger, healthier, and within 3 years of menopause thus matching more closely demographics of women in prior observational and epidemiological studies than women in the Women's Health Initiative hormone trials. KEEPS will provide information relevant to the critical timing hypothesis for MHT use in reducing risk for CVD.
Collapse
Affiliation(s)
- V M Miller
- Medical Science 4-62, College of Medicine, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Abstract
BACKGROUND Estrogen modulates antithrombotic characteristics of the vascular endothelium and the interaction of blood elements with the vascular surface. A marker of these modulatory activities is formation of cell-specific microparticles. This study examined the relationship between blood-borne microparticles and endogenous estrogen at menopause. METHODS Platelet activation and plasma microparticles were characterized from women being screened (n = 146) for the Kronos Early Estrogen Prevention Study. Women were grouped according to serum estrogen (< 20 pg/ml; low estrogen, n = 21 or > 40 pg/ml; high estrogen, n = 11). RESULTS Age, body mass index, blood pressure and blood chemistries were the same in both groups. No woman was hypertensive, diabetic or a current smoker. Platelet counts, basal and activated expression of P-selectin on platelet membranes were the same, but activated expression of glycoprotein IIb/IIIa was greater in the high-estrogen group. Numbers of endothelium-, platelet-, monocyte- and granulocyte-derived microparticles were greater in the low-estrogen group. Of the total numbers of microparticles, those positive for phosphatidylserine and tissue factor were also greater in the low-estrogen group. CONCLUSION These results suggest that, with declines in endogenous estrogen at menopause, numbers of procoagulant microparticles increase and thus may provide a means to explore mechanisms for cardiovascular risk development in newly menopausal women.
Collapse
Affiliation(s)
- M Jayachandran
- Department of Surgery, College of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | | | | | | |
Collapse
|
21
|
Miller VM, Lawrence DA, Mondal TK, Seegal RF. Reduced glutathione is highly expressed in white matter and neurons in the unperturbed mouse brain--implications for oxidative stress associated with neurodegeneration. Brain Res 2009; 1276:22-30. [PMID: 19393633 DOI: 10.1016/j.brainres.2009.04.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 03/13/2009] [Accepted: 04/12/2009] [Indexed: 10/20/2022]
Abstract
Oxidative stress is implicated in the pathogenesis of many neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. The depletion of glutathione (GSH) a powerful antioxidant renders cells particularly vulnerable to oxidative stress. Isolated neuronal and glial cell culture studies suggest that glia rather than neurons have greatest reserves of GSH, implying that neurons are most sensitive to oxidative stress. However, pathological in vivo studies suggest that GSH associated enzymes are elevated in neurons rather than astrocytes. The active, reduced form of GSH is rapidly degraded thus making it difficult to identify the location of GSH in post-mortem tissue. Therefore, to determine whether GSH is more highly expressed in neurons or astrocytes we perfused mouse brains with a solution containing NEM which reacts with the sulfhydryl group of GSH, thus locking the active form in situ, prior to immunostaining with an anti-GS-NEM antibody. We obtained brightfield and fluorescent digital images of sections stained with DAPI and antibodies directed against GS-NEM, glial fibrillary acidic protein (GFAP) in regions containing the hippocampus, striatum, frontal cortex, midbrain nuclei, cerebellum and reticular formation neurons. GSH was most abundant in neurons and white matter in all brain regions, and only in occasional astrocytes lining the third and fourth ventricles. High levels of GSH in neurons and white matter, suggests astrocytes rather than neurons may be particularly vulnerable to oxidative stress.
Collapse
Affiliation(s)
- V M Miller
- Biggs Laboratory, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201, USA.
| | | | | | | |
Collapse
|
22
|
Miller VM, Kalaria RN, Hall R, Oakley AE, Kenny RA. Medullary microvessel degeneration in multiple system atrophy. Neurobiol Dis 2007; 26:615-22. [PMID: 17466525 DOI: 10.1016/j.nbd.2007.03.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Revised: 02/13/2007] [Accepted: 03/07/2007] [Indexed: 11/29/2022] Open
Abstract
Multiple system atrophy (MSA) is a rare and fatal early-onset autonomic disorder which is characterised by Parkinsonism and orthostatic hypotension (OH). The pathophysiology of MSA is not fully understood but key features include the depletion of medullary autonomic neurons and presence of glial cellular inclusions. We hypothesise that the degeneration of medullary autonomic microvessels is an additional finding in MSA. Using digital pathology we quantified basement membrane collagen (Coll IV), smooth muscle actin (alpha-actin) and endothelial glucose transporter (Glut 1) expression in medullary autonomic nuclei of 8 MSA and 8 OH cases, compared with 12 controls with no autonomic dysfunction. We found decreased Coll IV (p=0.000) and Glut 1 (p=0.000) but not alpha-actin expression, in medullary autonomic nuclei of MSA, but not OH cases compared with control subjects. Medullary microvessel degeneration in MSA may be secondary to the primary neuro-glial pathogenesis of the disorder, and could accelerate its ageing-related progression.
Collapse
Affiliation(s)
- V M Miller
- Neurovascular Research Unit, Sir James Spence Institute, Royal Victoria Hospital, Newcastle upon Tyne, NE1 4LP, UK.
| | | | | | | | | |
Collapse
|
23
|
Harman SM, Brinton EA, Cedars M, Lobo R, Manson JE, Merriam GR, Miller VM, Naftolin F, Santoro N. KEEPS: The Kronos Early Estrogen Prevention Study. Climacteric 2005; 8:3-12. [PMID: 15804727 DOI: 10.1080/13697130500042417] [Citation(s) in RCA: 223] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Observational studies have indicated that hormone therapy given at or after menopause is linked to substantial reduction in cardiovascular disease and its risk factors. Recent findings from the Women's Health Initiative (WHI) clinical trial, however, indicate that combined estrogen plus progestin hormone therapy, as well as estrogen-alone hormone therapy (given to women without a uterus), is ineffective in preventing the new onset of cardiac events in previously healthy late menopausal women. Further, the secondary prevention trial, the Heart and Estrogen/progestin Replacement Study (HERS), also failed to demonstrate any benefit of initiation of hormone therapy in women with established coronary heart disease. In light of these results, a hypothesis has arisen that early initiation of hormone therapy, in women who are at the inception of their menopause, will delay the onset of subclinical cardiovascular disease in women. The rationale that earlier intervention than that performed in the WHI and HERS trials will provide cardiovascular benefit to women is the driving force behind the Kronos Early Estrogen Prevention Study, or KEEPS. KEEPS is a multicenter, 5-year clinical trial that will evaluate the effectiveness of 0.45 mg of conjugated equine estrogens, 50 microg weekly transdermal estradiol (both in combination with cyclic oral, micronized progesterone, 200 mg for 12 days each month), and placebo in preventing progression of carotid intimal medial thickness and the accrual of coronary calcium in women aged 42-58 years who are within 36 months of their final menstrual period. A total of 720 women are planned to be enrolled in 2005, with an anticipated close-out of the trial in 2010. This overview summarizes the recruitment and methodology of the KEEPS trial.
Collapse
|
24
|
Bracamonte MP, Jayachandran M, Rud KS, Miller VM. Acute effects of 17beta -estradiol on femoral veins from adult gonadally intact and ovariectomized female pigs. Am J Physiol Heart Circ Physiol 2002; 283:H2389-96. [PMID: 12388282 DOI: 10.1152/ajpheart.00184.2002] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Our experiments were designed to determine the acute effects of 17beta-estradiol on femoral veins from intact and ovariectomized female pigs. Rings of femoral veins with or without endothelium were suspended in organ chambers for measurement of isometric force. Concentration-response curves to 17beta-estradiol (10(-9) to 10(-5) M) were obtained in veins contracted with prostaglandin F(2alpha) in the absence and presence of inhibitors of either estrogen receptors (ICI-182780; 10(-5) M), nitric oxide synthase [N(G)-monomethyl-l-arginine (l-NMMA); 10(-4) M], soluble guanylate cyclase (1-H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one; 10(-5) M), or potassium channels (tetraethylammonium; 10(-2) M). Estrogen receptors were identified with the use of Western blotting and immunostaining in veins of both groups. 17beta-Estradiol caused acute endothelium-dependent relaxations in both groups. Relaxations to 17beta-estradiol were inhibited by l-NMMA and 1-H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one but not ICI-182780. Tetraethylammonium inhibited relaxations only in veins with endothelium from intact females. Results indicate that 17beta-estradiol causes acute endothelium-dependent relaxations in femoral veins. The relative contribution of nitric oxide and K(+) channels as mechanisms involved in relaxations to 17beta-estradiol in femoral veins is modulated by ovarian status.
Collapse
Affiliation(s)
- M P Bracamonte
- Department of Physiology and Biophysics, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
| | | | | | | |
Collapse
|
25
|
Abstract
Experiments were designed to determine how ovariectomy modulates mitogenic factors in platelets and how these factors affect proliferation of coronary arterial smooth muscle. Platelet-derived growth factors (PDGF(AB) and PDGF(BB)), transforming growth factors (TGF-beta(1) and TGF-beta(2)), and vascular endothelial growth factor (VEGF(165)) were quantified in platelet lysates and platelet-poor plasma from adult gonadally intact and ovariectomized female pigs by ELISA. Proliferation of cultured coronary arterial smooth muscle cells (SMCs) from both groups of pigs was determined in response to autologous or heterologous platelet lysates. Platelet concentrations of PDGF(BB), but not PDGF(AB), TGF-beta(1), and TGF-beta(2), increased with ovariectomy. VEGF(165) was not detected in platelets from either group. Proliferation of SMCs from ovariectomized females was significantly greater on exposure to autologous or heterologous platelet lysates than proliferation of SMCs from intact females. These results indicate that ovariectomy increases concentrations of PDGF(BB) in platelets. Higher levels of PDGF(BB) in platelets in synergy with other platelet-derived products could contribute to increased proliferative arterial response to injury after ovariectomy.
Collapse
Affiliation(s)
- M P Bracamonte
- Department of Physiology and Biophysics, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
| | | | | | | |
Collapse
|
26
|
Antoniucci D, Miller VM, Sieck GC, Fitzpatrick LA. Gender-related differences in proliferative responses of vascular smooth muscle cells to endothelin-1. Endothelium 2002; 8:137-45. [PMID: 11572475 DOI: 10.3109/10623320109165322] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Endothelin-1 is an endothelium-derived factor which alters tone and proliferation of vascular smooth muscle and has been implicated in the development of atherosclerosis. Estrogen modulates production of and contractile responses to endothelin-1. Since atherosclerosis is less in estrogen-replete women compared to men, experiments were designed to determine whether or not there were gender-associated differences in proliferative responses to endothelin-1 and effect of estrogen status on those responses. Proliferation of smooth muscle cells derived from coronary arteries of sexually mature, gondally intact male and female and oophorectomized female pigs was determined by thymidine incorporation in the absence and presence of endothelin-1 with and without 17beta-estradiol. Endothelin-1 (10(-9) M to 10(-7) M) significantly inhibited proliferation only in coronary smooth muscle cells from intact female pigs. Addition of beta-estradiol inhibited proliferation of cells from intact females but there was not a synergistic effect with endothelin-1. Gender associated inhibition of smooth muscle proliferation by endothelin-1 may contribute, in part, to cardioprotection noted in estrogen-replete states.
Collapse
Affiliation(s)
- D Antoniucci
- Department of Internal Medicine, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA
| | | | | | | |
Collapse
|
27
|
Lewis DA, Bracamonte MP, Rud KS, Miller VM. Selected contribution: Effects of sex and ovariectomy on responses to platelets in porcine femoral veins. J Appl Physiol (1985) 2001; 91:2823-30. [PMID: 11717251 DOI: 10.1152/jappl.2001.91.6.2823] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Estrogen replacement increases risk of venous thrombosis. In this study, we determined responses in vitro to platelets and platelet products in veins from adult male and intact and ovariectomized female pigs. When contracted with prostaglandin F(2alpha), platelets (25,000 platelets/microl) caused relaxation in veins with endothelium. Higher numbers of platelets caused contraction in veins with and without endothelium. In veins without endothelium, contractions were greater in veins from male than in veins from female pigs, and contractions in intact female pig veins were greater than in ovariectomized females pig veins. Platelet products 5-hydroxytryptamine and thromboxane (analog U-46619) caused comparable contractions in all veins; contractions to prostacyclin were less in veins from intact female pigs. ADP caused comparable endothelium-dependent relaxations in all groups. These relaxations were increased by indomethacin in veins from intact males and females; with inhibition of nitric oxide, relaxations were comparable in all groups. These results suggest that venous responses to platelets vary with sex and presence of ovaries in female pigs. These variations reflect differences in type and quantity of substances released from platelets as well as the sensitivity of the smooth muscle to some vasoactive substances. In addition, products of cyclooxygenase may reduce endothelium-dependent relaxations in veins.
Collapse
Affiliation(s)
- D A Lewis
- Department of Surgery, Mayo Clinic and Foundation, 200 First St. SW, Rochester, MN 55905, USA
| | | | | | | |
Collapse
|
28
|
Nemcova S, Noel AA, Jost CJ, Gloviczki P, Miller VM, Brockbank KG. Evaluation of a xenogeneic acellular collagen matrix as a small-diameter vascular graft in dogs--preliminary observations. J INVEST SURG 2001; 14:321-30. [PMID: 11905500 DOI: 10.1080/089419301753435693] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Autogenous veins are the materials of choice for arterial reconstruction. In the absence of autogenous material, prosthetic materials are used. However, vascular prostheses of less than 0.4 cm in diameter have low long-term patency. This study was designed to determine if cells would infiltrate an engineered xenogeneic biomaterial used as a small diameter arterial graft in dogs and, if so, to determine the phenotype of the infiltrating cells. Nine acellular xenogeneic grafts (0.4 cm in diameter, 5 cm long), composed of porcine collagen derived from the submucosa of the small intestine and type I bovine collagen, were implanted as end to-end interposition grafts in femoral arteries of five male mongrel dogs (total of nine grafts). All dogs received daily aspirin (325 mg). Patency of implanted grafts was monitored weekly by Duplex ultrasonography. After 9 weeks, or earlier in case of blood flow reduction by at least 75%, grafts were explanted and prepared for light or electron microscopy to evaluate cellularization. Eight of nine grafts remained patent up to 9 weeks. At explant, diameters were 0.31 +/- 0.02 cm at the midgraft, and 0.14 +/- 0.01 and 0.19 +/- 0.01 cm at the proximal and distal anastomoses. At explant, cells of mesenchymal origin (endothelial cells, smooth muscle cells, myofibroblasts) were embedded in the extracellular matrix of the graft scaffold. Minimal evidence of cellular inflammatory reaction and no aneurysmal dilatation or thrombus formation was detected. Variable degrees of hyperplasia were present at proximal and distal anastomoses. This preliminary study demonstrates that a collagen-based xenogeneic biomaterial provides a scaffold for cellularization when used for arterial reconstruction in dogs.
Collapse
Affiliation(s)
- S Nemcova
- Department of Surgery, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
| | | | | | | | | | | |
Collapse
|
29
|
Jayachandran M, Hayashi T, Sumi D, Iguchi A, Miller VM. Temporal effects of 17beta-estradiol on caveolin-1 mRNA and protein in bovine aortic endothelial cells. Am J Physiol Heart Circ Physiol 2001; 281:H1327-33. [PMID: 11514304 DOI: 10.1152/ajpheart.2001.281.3.h1327] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Endothelial nitric oxide synthase (eNOS) is regulated both by caveolin-1 and 17beta-estradiol (E(2)). Temporal relationships between effects of estrogen on caveolin-1 and nitric oxide (NO) are not known. Therefore, this study was designed to determine whether estrogen regulates caveolin-1 and, if so, whether such regulation corresponds to changes in nitrite/nitrate (NO(x)) production. Bovine aortic endothelial cells (BAECs) were cultured in the absence and presence of 17beta-estradiol or 17alpha-estradiol (10(-8) and 10(-10) M) for 12, 24, and 48 h. eNOS protein expression and NO(x) production increased significantly after 24 h but not after 12-h treatment with 17beta- and not 17alpha-estradiol. Both mRNA and protein for caveolin-1 were increased significantly only after 48-h treatment with E(2), but eNOS protein and NO(x) production were decreased compared with cells treated for 24 h. These increases in caveolin-1 were inhibited by the estrogen receptor antagonist ICI-182,780 (10(-6) M). Results of this study suggest that E(2) stimulates caveolin-1 transcription and translation through estrogen receptor-mediated mechanisms. The results further suggest that estrogen may indirectly regulate NO(x) through caveolin-1 expression, which inhibits eNOS catalytic activity.
Collapse
Affiliation(s)
- M Jayachandran
- Department of Geriatrics, Nagoya University School of Medicine, Nagoya 466-8550, Japan
| | | | | | | | | |
Collapse
|
30
|
Luyer MD, Khosla S, Owen WG, Miller VM. Prospective randomized study of effects of unopposed estrogen replacement therapy on markers of coagulation and inflammation in postmenopausal women. J Clin Endocrinol Metab 2001; 86:3629-34. [PMID: 11502788 DOI: 10.1210/jcem.86.8.7768] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Estrogen replacement therapy decreases the risk of arterial disease while at the same time increases the risk for venous thrombosis. Whether a common mechanism(s) of coagulation and inflammation contributes to both responses is unclear. This study determined simultaneous effects of estrogen replacement therapy on regulators of the direct (extrinsic) pathway for activation of coagulation, coagulation, and the acute phase response. Plasma from 26 postmenopausal women without risk factors for cardiovascular disease was collected before (baseline) and after 3 months of treatment with either conjugated equine estrogen (Premarin, 0.625 mg/d) or placebo. Plasma lipids, tissue factor pathway inhibitor antigen and activity, plasminogen, prothrombin, P-selectin, alpha1-protease inhibitor, and C-reactive protein were measured. Estrogen replacement therapy significantly reduced mean concentrations of tissue factor pathway inhibitor (antigen and activity; P < 0.001), which were correlated significantly to decreases in low density lipoprotein (r2 = 0.71). Plasminogen and C-reactive protein increased significantly. Other parameters were unchanged. The results of this prospective study suggest that 3 months of estrogen replacement therapy in healthy postmenopausal women decreases low density lipoprotein with simultaneous decreases in tissue factor pathway inhibitor, a major inhibitor of the extrinsic coagulation pathway, and increases C-reactive protein, a component of the acute phase response. Concomitant changes in these parameters may reduce the risk for arterial disease while altering the threshold for thrombotic events.
Collapse
Affiliation(s)
- M D Luyer
- Department of Surgery, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
| | | | | | | |
Collapse
|
31
|
Abstract
Mechanisms by which estrogen reduces the risk of arterial disease, while simultaneously increasing the risk of venous thrombosis in postmenopausal women, are not clearly understood. In addition to providing beneficial arterial effects on the lipid profile, estrogen both increases production of nitric oxide and decreases production of endothelin-1 from arterial endothelium, decreases intracellular calcium in arterial smooth muscle and might favor fibrinolysis. All of these effects could act in concert to protect against development of arterial occlusive disease. However, comparable effects on venous endothelium and smooth muscle have not been studied systematically, and although blood elements such as platelets and leukocytes contain estrogen receptors, much remains to be learned about the effect that dose and duration of estrogen-treatment might have upon these cells. An integrative approach to understanding the actions of estrogen on the venous system and the interaction of blood elements with the vascular wall is necessary before new therapeutic interventions will provide arterial protection with no risk of venous thrombosis.
Collapse
Affiliation(s)
- M P Bracamonte
- Dept of Physiology and Biophysics, Mayo Clinic, 55905, Rochester, MN, USA
| | | |
Collapse
|
32
|
Ugurlu MM, Griffin MD, O'Brien T, Tazelaar HD, Miller VM, McGregor CG. The effects of CTLA-4Ig on acute lung allograft rejection: a comparison of intrabronchial gene therapy with systemic administration of protein. Transplantation 2001; 71:1867-71. [PMID: 11455274 DOI: 10.1097/00007890-200106270-00029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Blockade of T-cell costimulation by local delivery of an adenoviral vector encoding for CTLA-4Ig and systemic administration of the protein are compared in a rat lung allograft model. METHODS Left lungs of Brown Norway rats (RT1n) were transplanted into Lewis (RT11) recipients in four groups of six animals each: 1) no treatment; 2) intrabronchial transduction of donor lung with adenovirus encoding mCTLA-4Ig (adeno-mCTLA-4Ig); 3) intrabronchial transduction with empty adenovirus; and 4) intraperitoneal injection of mCTLA-4Ig. Grading of rejection, mCTLA-4Ig measurement in serum and bronchial washings, RT-PCR for virally encoded transcripts, and immunohistochemistry for mCTLA-4Ig were carried out 4 days later. RESULTS Intrabronchial transduction with adeno-mCTLA-4Ig resulted in detectable transgene expression in graft tissue and bronchial fluid but not in serum. Significant reduction in rejection grade (from grade 3 to 2) occurred after systemic mCTLA-4Ig but not adeno-mCTLA-4Ig transduction. CONCLUSION Local expression of immunomodulatory proteins can be achieved within lung allografts by intrabronchial delivery of adenoviral vector but may not significantly modify acute rejection.
Collapse
Affiliation(s)
- M M Ugurlu
- Department of Surgery, Mayo Transplant Center, Mayo Clinic, Rochester, MN 55905
| | | | | | | | | | | |
Collapse
|
33
|
Jeppsson A, Pellegrini C, O'Brien T, Miller VM, Tazelaar HD, Taner CB, McGregor CG. Gene transfer of endothelial nitric oxide synthase to pulmonary allografts: impact on acute rejection. Transpl Int 2001; 13 Suppl 1:S591-6. [PMID: 11112080 DOI: 10.1007/s001470050409] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Experiments were designed to study whether overexpression of nitric oxide (NO) from endothelial nitric oxide synthase (eNOS) affects acute rejection. Allogenic, orthotopic single-lung transplantation was performed after transbronchial adenoviral-mediated gene transfer (3 x 10(8) pfu) of either of eNOS or beta-galactosidase to donor lungs of rats (n = 6 each). No immunosuppression was used. After 4 days, transplanted lungs were prepared for enzyme activity, cGMP and histology. Calcium-dependent NOS activity, reflecting eNOS, was greater in eNOS-transduced lungs (587 +/- 97 vs 2.1 +/- 1.4 pmol/mg protein per h, P <0.001). In contrast, calcium-independent NOS activity, reflecting iNOS, was comparable. Concentrations of cGMP were higher in eNOS-transduced lungs (13.2 +/- 2.3 vs 4.9 +/- 0.5 pmol/mg protein). Positive immunostaining for eNOS was present in pneumocytes only in eNOS-transduced lungs. No difference in histological grade of rejection was observed. eNOS gene transfer to pulmonary allografts results in a functionally active transgene product and increased NO production. Increasing NO from eNOS does not affect histogically identified acute rejection.
Collapse
Affiliation(s)
- A Jeppsson
- Mayo Clinic and Foundation, Rochester, Minnesota, USA.
| | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
PURPOSE Experiments were designed to determine effects of dietary supplementation with L -arginine on structure and function of flow-restricted vein grafts. METHODS Saphenous veins were placed as bilateral interposition grafts in femoral arteries of two groups of adult male mongrel dogs; one group was maintained on a normal diet (control), the other group supplemented with L -arginine (200 mg/kg per day) beginning 1 week before surgery. In each dog, flow was reduced by 50% in one graft by placing an adjustable clamp on the artery distal to the distal anastomosis. Plasma amino acids and oxidized products of nitric oxide (NO(x )) were measured before and after L -arginine feeding. At postoperative week 4, grafts were removed and prepared for organ chamber studies to determine functions of the endothelium or smooth muscle and for histology. RESULTS Plasma L -arginine increased within 3 hours after feeding and increased from 141 +/- 8 nmol/mL to 169 +/- 11 nmol/mL (n = 6) after 5 weeks of supplementation. Plasma ornithine and citrulline paralleled arginine, whereas circulating NO(x ) was unchanged. Maximal contractions to 60 mmol/L KCl were reduced in grafts from L -arginine-fed dogs. Endothelium-dependent relaxations to the calcium ionophore A23187 and relaxations of the smooth muscle NO were reduced in grafts from L -arginine-fed dogs. Neointimal hyperplasia was increased in grafts with reduced flow and not affected by arginine feeding. CONCLUSIONS Dietary supplementation with L -arginine did not increase plasma NO in dogs with peripheral vein grafts or increase endothelium-dependent relaxations in control or flow-restricted grafts. Therefore, dietary supplementation with L -arginine may not improve long-term functions of flow-restricted peripheral bypass grafts.
Collapse
Affiliation(s)
- M E Landis
- Department of Surgery, Mayo Foundation, Rochester, MN, USA
| | | | | | | |
Collapse
|
35
|
Taner CB, Severson SR, Best PJ, Lerman A, Miller VM. Treatment with endothelin-receptor antagonists increases NOS activity in hypercholesterolemia. J Appl Physiol (1985) 2001; 90:816-20. [PMID: 11181588 DOI: 10.1152/jappl.2001.90.3.816] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In experimental hypercholesterolemia, endothelium-dependent relaxations decrease, as does endothelial immunoreactivity for nitric oxide (NO) synthase (NOS; eNOS) in coronary arteries. Systemic levels of NO also decrease with concomitant elevations in systemic circulating levels of endothelin (ET)-1. Chronic treatment of hypercholesterolemic pigs with ET-receptor antagonists increases circulating NO and improves endothelium-dependent relaxations. Mechanisms causing these increases are not known. Therefore, experiments were designed to test the hypothesis that chronic administration of ET-receptor antagonists to hypercholesterolemic pigs increases NO production through increases in NOS activity. Female juvenile pigs were fed a 2% cholesterol atherogenic diet and were randomly allocated to receive no treatment (controls), a selective ET(A)-receptor antagonist (ABT-624), or a combined ET(A) + ET(B)-receptor antagonist (RO-48-5695) daily for 12 wk. After 12 wk, endothelial cells from thoracic aorta were prepared for measurement of eNOS mRNA or eNOS activity. Total cholesterol, low-density-lipoprotein cholesterol, and concentrations of ET-1 were significantly higher in all three groups at 12 wk compared with baseline levels. Circulating plasma-oxidized products of NO (NOx) increased with ET-receptor blockade. NOS mRNA was similar among groups. Total and Ca-dependent NOS activity was significantly higher in aortic endothelial cells from the ET(A) + ET(B)-treated pigs compared with those treated with ET(A) antagonist alone. These results suggest that changes in systemic NOx after chronic inhibition of ET(A) + ET(B) receptors in hypercholesterolemia may result from posttranscriptional changes in NOS.
Collapse
MESH Headings
- Animals
- Aorta, Thoracic
- Cholesterol/blood
- Cholesterol, Dietary
- Cholesterol, HDL/blood
- Cholesterol, LDL/blood
- Diet, Atherogenic
- Endothelin Receptor Antagonists
- Endothelium, Vascular/enzymology
- Female
- Gene Expression Regulation, Enzymologic/drug effects
- Hypercholesterolemia/blood
- Hypercholesterolemia/enzymology
- Hypercholesterolemia/physiopathology
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type III
- RNA, Messenger/genetics
- Receptor, Endothelin A
- Receptor, Endothelin B
- Sulfonamides/pharmacology
- Swine
- Transcription, Genetic/drug effects
- Triglycerides/blood
Collapse
Affiliation(s)
- C B Taner
- Department of Surgery, Division of Cardiovascular Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
| | | | | | | | | |
Collapse
|
36
|
Abstract
Experiments were designed to determine the effects of nicotine treatment on the functions of saphenous veins used for coronary artery bypass grafts in dogs. Dogs received either no treatment or transdermal nicotine for 5 weeks at doses of 11 mg, 22 mg or 44 mg/day. Saphenous veins were removed and suspended for the measurement of isometric force in organ chambers. Endothelium was removed mechanically from some rings. N(G)-mono-methyl-L-arginine (L-NMMA; 10(-4) M) was used to inhibit the production of nitric oxide. Contractions to alpha2-adrenergic stimulation were decreased in veins from dogs treated with a 22-mg/day dose of transdermal nicotine. In addition, endothelium-dependent relaxations to adenosine-diphosphate (10(-8)-10(-4) M) and the calcium ionophore A23,187 (10(-8)-10(-6) M) were decreased in veins from dogs with a 22-mg/day dose and increased in veins from dogs treated with a 44-mg/day dose. These relaxations were inhibited by L-NMMA. Plasma concentrations of oxidized products of nitric oxide were decreased only in dogs treated with 22 mg/day of nicotine. The relaxation of rings without endothelium (direct response on the smooth muscle) to nitric oxide were not altered by nicotine treatment. These results suggest that the short-term treatment of dogs with intermediate (22 mg/day) but not low (11 mg/day) or high (44 mg/day) doses of transdermal nicotine decreases the endothelial function of veins used for coronary artery bypass grafts. Therefore, changes in plasma products of nitric oxide and endothelium-dependent relaxations mediated by nitric oxide are related to the dose of nicotine treatment.
Collapse
Affiliation(s)
- W D Clouse
- Department of Surgery, Mayo Clinic and Foundation, Rochester, MN 55905, USA
| | | | | | | |
Collapse
|
37
|
Jeppsson A, Pellegrini C, Lee R, O'Brien T, Miller VM, Tazelaar HD, McGregor CG. Improved efficiency of gene transfer to the transplanted lung by retrograde vascular gene delivery. Transpl Int 2001; 13:241-6. [PMID: 10959475 DOI: 10.1007/s001470050697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Experiments were designed to evaluate the efficiency of antegrade compared to retrograde vascular gene transfection of donor lungs used for transplantation. Rat donor lungs (n = 5/group) were transduced with an adenoviral vector encoding for beta-galactosidase (AdbetaGal), either antegrade in the pulmonary artery (Group A, 3 x 10(8) pfu, Group B, 3 x 10(9) pfu) or retrograde into the pulmonary vein (Group C, 3 x 10(8) pfu), immediately after pneumoplegia. After storage at 4 degrees C for 1 h, the transduced lungs were transplanted orthotopically in syngeneic animals. The lungs were assessed for transgene expression by ELISA and X-Gal-staining at day 7 after operation. Inflammation was graded based on the extent of inflammatory cell infiltration. Transgene expression was similar between Groups A (1.7 +/- 0.7 ng/mg protein) and B (2.1 +/- 1.0 ng/mg protein). With retrograde delivery, there was a four-fold (8.3 +/- 2.6 ng/ mg protein) increase (P < 0.05) in transgene expression compared to either group A or B. In all groups, pneumocytes were transduced most frequently. The degree of inflammation correlated positively with the extent of transgene expression (r = 0.75, P < 0.01). The efficiency of vascular gene delivery to transplanted lungs can be improved by retrograde delivery of the vector via the pulmonary vein. Transgene expression predominates in pneumocytes following both antegrade and retrograde delivery. The severity of inflammation in the transplanted lung appears to correlate with the extent of transgene expression.
Collapse
Affiliation(s)
- A Jeppsson
- Department of Surgery, Mayo Clinic and Foundation, Rochester, MN 55905, USA
| | | | | | | | | | | | | |
Collapse
|
38
|
Kalra M, Jost CJ, Severson SR, Miller VM. Adventitial versus intimal liposome-mediated ex vivo transfection of canine saphenous vein grafts with endothelial nitric oxide synthase gene. J Vasc Surg 2000; 32:1190-200. [PMID: 11107092 DOI: 10.1067/mva.2000.109211] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE Experiments were designed (1) to evaluate liposome-mediated endothelial constitutive nitric oxide synthase (ecNOS) transfection in vein grafts and (2) to compare intimal and adventitial routes of transfection. METHODS Male mongrel dogs (N = 36) underwent bilateral femoral artery bypass grafting with the lateral saphenous vein. In each animal one vein was transfected with plasmid (pVR1012) containing the ecNOS gene, and another vein was transfected with plasmid alone (control). Gene transfer was performed from either the intimal surface (Group I, n = 18) or the adventitial surface (Group II, n = 18). In each group there were three transfection subgroups (n = 6 each): (a ) 10 microg/mL naked plasmid DNA, (b ) 10 microg/mL plasmid DNA + liposome (LipofectAMINE PLUS), and (c ) 100 microg/mL plasmid DNA + LipofectAMINE PLUS. Grafts were harvested on the third postoperative day, and the transfection was assessed with molecular techniques and enzyme assay for activity of NOS by conversion of tritiated l-arginine to tritiated l-citrulline. Proliferating cells were quantified with a digital analysis of histologic sections after nuclear antigen Ki-67 (MIB1) immunohistochemistry. RESULTS Transgene was identified with polymerase chain reaction in all ecNOS-transfected grafts, regardless of transfection modality. However, significant transcription of the ecNOS transgene was observed only in Group IIc (mean ecNOS messenger RNA, 8.7+/-1.7 vs. 3.1+/-0.7 x 10(-2) attomole/microL, in transfected compared with control grafts, respectively, P =.01). NOS activity increased approximately twofold in this group (11.58+/-2.1 and 6.3+/-1.0 pmol tritiated l-citrulline per milligram protein per hour in transfected and control grafts, respectively, P = .05). Numbers of proliferating cells did not differ among ecNOS-transfected and control grafts in any transfection group. CONCLUSION These results suggest that ecNOS transfection of vein grafts is feasible through intimal and adventitial routes with naked DNA or a liposomal vector. However, efficient transcription of the transgene is evident at postoperative day 3 only after adventitial transfection of 100 microg/mL of the gene.
Collapse
Affiliation(s)
- M Kalra
- Department of Surgery and Biophysics and Physiology, Mayo Clinic and Foundation, Rochester, MN, USA
| | | | | | | |
Collapse
|
39
|
Mathew V, Miller VM, Hasdai D, Barber DA, Holmes DR, Lerman A. Increased coronary effects of stimulation of endothelin-B receptor in experimental hypercholesterolemia. Coron Artery Dis 2000; 11:585-92. [PMID: 11107505 DOI: 10.1097/00019501-200012000-00003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [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] [Indexed: 11/26/2022]
Abstract
BACKGROUND Vasoconstriction in response to endothelin-1 has been shown to be primarily related to its effects on the endothelin-A receptor. Experimental hypercholesterolemia is associated with an increase in coronary vasoconstrictor response to endothelin-1 in vivo, although the relative contributions of subtypes of endothelin receptor in this model remain unknown. OBJECTIVE To test the hypothesis that there is an increase in coronary vasoconstriction in response to stimulation of endothelin-B receptor in hypercholesterolemia, which might be related to attenuation of activity of endothelin-derived relaxing factor. METHODS We infused 5 ng/kg/min sarafotoxin, a specific endothelin-B receptor agonist, or 50 micrograms/kg/min NG-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of nitric oxide synthase, into the left anterior descending coronary arteries of pigs before and after feeding them a cholesterol-rich diet for 10 weeks. RESULTS There was a significant increase in serum level of cholesterol. After 10 weeks, infusion of sarafotoxin resulted in an accentuated decrease in coronary blood flow (CBF) compared with baseline (decreases by 60 +/- 7 versus 34 +/- 6%, P < 0.05). There was no significant difference between the effects on diameter of coronary arteries for the two time periods. The effect of L-NMMA on CBF was attenuated after 10 weeks (by 5 +/- 10.1 versus 45.6 +/- 4.7%, P < 0.05). Endothelin-receptor status of epicardial coronary arteries remained unchanged. Sarafotoxin and L-NMMA were co-infused at the above-mentioned doses into normolipidemic animals; the decrease in CBF in response to this co-infusion was comparable to the decrease observed with sarafotoxin alone in hypercholesterolemic animals (decreases of 67 +/- 5 versus 60 +/- 7, NS). CONCLUSIONS The present results demonstrate that selective stimulation of the endothelin-B receptor increases coronary vasoconstriction in experimental hypercholesterolemia, primarily at the level of the microvasculature. These findings may be related to the attenuation of activity of endothelin-derived relaxing factor in this model, and support the hypothesis that endothelin-B receptor plays a role in the regulation of coronary vascular tone in pathophysiologic states.
Collapse
Affiliation(s)
- V Mathew
- Department of Internal Medicine, Mayo Foundation, Rochester, Minnesota, USA.
| | | | | | | | | | | |
Collapse
|
40
|
Tonnessen BH, Severson SR, Hurt RD, Miller VM. Modulation of nitric-oxide synthase by nicotine. J Pharmacol Exp Ther 2000; 295:601-6. [PMID: 11046094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Effects of nicotine on arterial endothelium-dependent relaxations mediated by nitric oxide are controversial. Experiments were designed to test the hypothesis that nicotine can directly alter activity of endothelial nitric-oxide synthase (eNOS). NOS from aortic endothelial cells of untreated dogs and recombinant eNOS, neuronal NOS, and inducible NOS were used for these experiments. NOS activity was determined as conversion of L-[(3)H]arginine to L-[(3)H]citrulline in the absence or presence of nicotine (10(-7)-10(-3) M) in vitro. In separate assays, concentrations of cofactors NADPH, FAD, and tetrahydrobioprotein were reduced by half to assess for possible interaction with nicotine. With enzyme from aortic endothelial cells, total and calcium-dependent accumulation of citrulline increased by 30% in the presence of 10(-5) M nicotine. Nicotine dose dependently also increased citrulline accumulation by recombinant eNOS and neuronal NOS but not inducible NOS. Effects of nicotine on accumulation of citrulline by isolated eNOS and recombinant eNOS were further modulated by changes in the concentration of NADPH in the incubation solution. Our data demonstrate a significant effect of nicotine on eNOS-mediated citrulline accumulation. These results suggest that effects of nicotine on production of nitric oxide may depend on NADPH or oxygen radical interactions with NOS and thus may explain, in part, inconsistent findings of changes in production of endothelium-derived nitric oxide with nicotine administration.
Collapse
Affiliation(s)
- B H Tonnessen
- Department of Surgery, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
| | | | | | | |
Collapse
|
41
|
Kalra M, Miller VM. Early remodeling of saphenous vein grafts: proliferation, migration and apoptosis of adventitial and medial cells occur simultaneously with changes in graft diameter and blood flow. J Vasc Res 2000; 37:576-84. [PMID: 11146412 DOI: 10.1159/000054091] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND This study was designed to determine how migration and proliferation of adventitial and medial cells correlate temporally with hemodynamic characteristics including changes in diameter and blood flow in vein grafts. METHODS Male mongrel dogs underwent end-to-side reversed saphenous vein bypass grafting across a ligated femoral artery. Hemodynamic parameters were assessed by duplex ultrasound. Proliferating cells were labeled 24-48 h after grafting with 5-bromo-2'-deoxyuridine (BrdU). Grafts were removed on postoperative days 2, 5, 7 and 14. Immunohistochemistry was performed on graft sections with antibodies to nuclear antigen Ki-67 (MIB-1), BrdU and smooth muscle cell markers. Apoptosis was identified by modified TUNEL staining. Proliferating/apoptotic cells were quantified digitally. RESULTS Mean luminal cross-sectional area, blood flow and velocity increased from day 2 to 7. Cell proliferation was evident in adventitia and media on day 2, maximum on day 5 and decreased significantly by day 14. Apoptosis was maximum on day 5. Early proliferating cells (BrdU labeled) localized in the adventitia and media on day 2 were more prevalent in the neointima on days 5-14 suggesting inward migration. On day 2, proliferating cells stained positive only for vimentin. By days 5-14, proliferating cells stained for alpha-smooth-muscle actin, a phenotype characteristic of myofibroblasts. CONCLUSION These results indicate that cell proliferation and apoptosis occur simultaneously within the adventitia and media of the vein during the first week following grafting, when changes in diameter and blood flow are greatest. In addition, proliferating adventitial cells subsequently migrate inwards to contribute to the formation of neointima.
Collapse
Affiliation(s)
- M Kalra
- Department of Surgery, Mayo Clinic and Foundation, Rochester, MN 55905, USA
| | | |
Collapse
|
42
|
Miller VM, Vanhoutte PM. Prostaglandins but not nitric oxide are endothelium-derived relaxing factors in the trout aorta. Acta Pharmacol Sin 2000; 21:871-6. [PMID: 11501036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
AIM To identify the type of prostanoids produced by endothelial cells of trout aorta and to determine whether or not the smooth muscle responds to nitric oxide. METHODS Ventral aortas, with and without endothelium from rainbow trout (S gairdneri), were incubated in a buffered salt solution. RESULTS Addition of the calcium ionophore A23187 caused a significant increase in prostaglandin E's and a consistent increase in the stable metabolite of prostacyclin (6-keto-prostaglandin F1 alpha) in the incubation media only when the endothelium was present. This production was inhibited by methylene blue (10 mumol/L). In rings of trout aorta without endothelium suspended for the measurement of isometric force in organ chambers, prostacyclin and prostaglandin E1 but not prostaglandin E2 caused concentration-dependent decreases in tension when the rings were contracted with acetylcholine. The smooth muscle did not relax to nitric oxide but did so to sodium nitroprusside. Relaxations to the latter nitrovasodilator were not inhibited by methylene blue. Descending aorta without endothelium from frogs relaxed in a concentration-dependent manner to nitric oxide. CONCLUSION Predominant endothelium-derived relaxing factors in trout aorta are prostaglandins, the synthesis of which can be inhibited by methylene blue. A phylogenetic appearance of nitric-oxide sensitive mechanism for vasodilatation, perhaps is associated with the transition from water to air respiration.
Collapse
Affiliation(s)
- V M Miller
- Departments of Surgery, and Physiology and Biophysics, Mayo Clinic and Foundation, 200 First Street SW, Rochester, MN 55905, USA.
| | | |
Collapse
|
43
|
Miller VM, Clouse WD, Tonnessen BH, Boston US, Severson SR, Bonde S, Rud KS, Hurt RD. Time and dose effect of transdermal nicotine on endothelial function. Am J Physiol Heart Circ Physiol 2000; 279:H1913-21. [PMID: 11009480 DOI: 10.1152/ajpheart.2000.279.4.h1913] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [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] [Indexed: 11/22/2022]
Abstract
Nicotine patches are available as an over-the-counter medication for aid in smoking cessation. This study was designed to determine how nicotine patch therapy over time and dose ranges used in smoking cessation programs in humans affects endothelium-dependent relaxations. Dogs were treated with nicotine patches (11, 22, or 44 mg/day) for 2 and 5 wk. Circulating nicotine and oxidized products of nitric oxide (NOx) were measured. Coronary arteries were prepared for measurement of isometric force and aortic endothelial cells were prepared for measurement of mRNA or NO synthase (NOS) activity. Circulating nicotine increased with increasing concentrations of nicotine patches. After 5 wk of treatment with 22 mg/day patches, circulating NOx was reduced but NOS activity was increased. NOS mRNA was similar among groups. Only after 5 wk of treatment with 22 mg/day patches were endothelium-dependent relaxations reduced to alpha(2)-adrenergic agonists, ADP, and the calcium ionophore A-23187. These results suggest a time and biphasic dose effect of nicotine treatment on endothelium-dependent responses that may be related to bioavailability of NO. This complex relationship of duration and dose of nicotine treatment may explain, in part, discrepancies in effects of nicotine on endothelium-dependent responses.
Collapse
Affiliation(s)
- V M Miller
- Departments of Surgery, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Clouse WD, Yamaguchi H, Phillips MR, Hurt RD, Fitzpatrick LA, Moyer TP, Rowland C, Schaff HV, Miller VM. Effects of transdermal nicotine treatment on structure and function of coronary artery bypass grafts. J Appl Physiol (1985) 2000; 89:1213-23. [PMID: 10956371 DOI: 10.1152/jappl.2000.89.3.1213] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Smoking is a major risk factor for failure of coronary artery bypass grafts (CABG). Experiments were designed to determine effects of transdermal nicotine, independent of smoking, on structure and function of CABG. Saphenous veins were placed as CABG in untreated dogs (control) or in dogs treated with transdermal nicotine (one 11-mg or two 22-mg patches/day) for 5 wk. Serum nicotine and plasma nitric oxide were measured. Grafts were removed and prepared for organ chamber studies and histology. Serum nicotine averaged 12.1 and 118.7 ng/ml in the 11 mg/day and 44 mg/day groups, respectively. Plasma nitric oxide was higher in dogs treated with 11 mg/day doses compared with controls. In organ chamber studies, endothelium-dependent relaxations to thrombin and A-23187 and endothelium-independent relaxations to nitric oxide were greatest in grafts from dogs treated with 11 mg/day doses. Intimal thickness of the grafts were similar among groups. However, staining for bone sialoprotein was increased in the media of grafts from the 11 mg/day treatment group. These data suggest that transdermal nicotine in doses comparable and double to those used for conventional smoking cessation treatment in humans does not adversely affect early patency of canine CABG up to 4 wk postoperatively. Transdermal nicotine, however, may increase production of and response to nitric oxide in bypass grafts.
Collapse
Affiliation(s)
- W D Clouse
- Division of Cardiovascular Surgery, Department of Surgery, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Abstract
Nerve root dysfunction and sciatic pain in disc herniation are considered to be caused by mechanical compression and related to the presence of nucleus pulposus in the epidural space. Autologous nucleus pulposus has been shown to induce endoneural edema and to decrease nerve-conduction velocity in spinal nerve roots in experimental disc herniation models, and inflammatory mediators have been suggested to be involved in these mechanisms. Nitric oxide, a potent inflammatory mediator, is implicated in vasoregulation, neurotransmission, and neuropathic pain. Nitric oxide synthesis can be induced by different cytokines, e.g., tumor necrosis factor-alpha, which recently was shown to be of pathophysiological importance in experimental disc herniation. The enzyme nitric oxide synthase mediates the production of nitric oxide. Three series of experiments were performed in rat and pig disc herniation models to (a) investigate nitric oxide synthase activity in spinal nerve roots after exposure to autologous nucleus pulposus and (b) evaluate the effects of systemic treatment with aminoguanidine, a nitric oxide synthase inhibitor, on vascular permeability and nerve-conduction velocity. In a disc herniation model in the rat, calcium-independent nitric oxide synthase activity was measured in nerve roots exposed to nucleus pulposus; however, no nitric oxide synthase activity was detected in nerve roots from animals that underwent a sham operation, reflecting increased inducible nitric oxide synthase activity. In nucleus pulposus-exposed spinal nerve roots in the pig, the edema was less severe after systemic aminoguanidine administration than without aminoguanidine treatment. Aminoguanidine treatment also significantly reduced the negative effect of nucleus pulposus on nerve-conduction velocity in spinal nerve roots in the pig. These results demonstrate that nucleus pulposus increases inducible nitric oxide synthase activity in spinal nerve roots and that nitric oxide synthase inhibition reduces nucleus pulposus-induced edema and prevents reduction of nerve-conduction velocity. Furthermore, the results suggest that nitric oxide is involved in the pathophysiological effects of nucleus pulposus in disc herniation.
Collapse
Affiliation(s)
- H Brisby
- Department of Orthopaedics, Göteborg University, Sahlgrenska University Hospital, Sweden.
| | | | | | | | | | | |
Collapse
|
46
|
|
47
|
Kamath PS, Carpenter HA, Lloyd RV, McKusick MA, Steers JL, Nagorney DM, Miller VM. Hepatic localization of endothelin-1 in patients with idiopathic portal hypertension and cirrhosis of the liver. Liver Transpl 2000; 6:596-602. [PMID: 10980059 DOI: 10.1053/jlts.2000.9735] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [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] [Indexed: 02/07/2023]
Abstract
Endothelin-1 (ET-1) may mediate increased resistance to hepatic sinusoidal blood flow. We evaluated the hepatic distribution of ET-1 in patients with idiopathic portal hypertension (IPH), in which liver architecture may be normal, and in patients with cirrhosis, in which distortion of hepatic sinusoidal architecture is prominent. Immunohistochemistry and in situ hybridization were used to localize ET-1 in hepatic tissue of patients with IPH and cirrhosis. ET-1 was measured in plasma from a peripheral vein, the hepatic vein, and the portal vein of patients with cirrhosis of the liver and controls. On immunohistochemistry and in situ hybridization, ET-1 was localized to periportal hepatocytes and sinusoidal cells in patients with IPH and cirrhosis. Minimal positive staining for ET-1 was observed in control livers. Plasma ET-1 levels were significantly greater in patients with cirrhosis than in controls. In patients with cirrhosis, ET-1 was greater in the hepatic vein compared with the portal vein. However, the level of plasma ET-1 in patients with cirrhosis did not correlate with either the presence of ascites or portacaval pressure gradient. We conclude that in IPH, ET-1 is localized to sites in which it can modulate intrahepatic resistance. In late stages of cirrhosis, ET-1 may not modulate resistance. We speculate that vascular resistance in late stages of cirrhosis probably results from distortion of hepatic architecture.
Collapse
Affiliation(s)
- P S Kamath
- Departments of Medicine, Mayo Clinic, Rochester, MN 55905, USA.
| | | | | | | | | | | | | |
Collapse
|
48
|
Rhodes JM, Cho JS, Gloviczki P, Mozes G, Rolle R, Miller VM. Thrombolysis for experimental deep venous thrombosis maintains valvular competence and vasoreactivity. J Vasc Surg 2000; 31:1193-205. [PMID: 10842157 DOI: 10.1067/mva.2000.104421] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE Thrombolysis protects the structural and functional integrity of vein wall in an experimental model of acute deep venous thrombosis (DVT) immediately after treatment, but late sequelae have not been studied. We designed experiments to compare the effects of thrombolysis and surgical thrombectomy at 4 weeks after the treatment of DVT. METHODS DVT was produced bilaterally in male mongrel dogs by proximal and distal femoral vein ligation. Five dogs underwent sham operation. After 48 hours, the ligatures were removed, and the thrombosis was treated with either Fogarty balloon catheter thrombectomy (shear force, 60 g; n = 6) or catheter-directed urokinase infusion (4000 U/min for 90 minutes; n = 6). At 4 weeks, patency and valvular competence were determined by duplex ultrasound scanning. Thrombogenicity was studied by the measurement of radiolabeled fibrin and platelet deposition. Veins were explanted and prepared for histologic examination, scanning electron microscopy, and functional studies in organ chambers. RESULTS All veins were patent at 1 month. Recanalized thrombus was observed histologically in four (66%) thrombectomized veins, one (17%) thrombolyzed vein, and none of the sham-operated veins (P =.04). Scanning electron microscopy demonstrated similar luminal endothelial cell loss (11%-25%) in all three groups. Platelet and fibrin depositions were not different among groups. Valvular incompetence (reflux duration, >0.5 sec) did not differ significantly in the groups (thrombectomized veins, 2 of 12 (17%); thrombolyzed veins, 0 of 12 (0%); P = NS). In organ chamber studies, endothelium-dependent relaxations to calcium ionophore, but not adenosine diphosphate, were inhibited by an antagonist of nitric oxide production after thrombectomy (P <.05, thrombectomy vs sham- and thrombolysis-treated veins). All veins relaxed to exogenous nitric oxide. CONCLUSION Both thrombectomy and thrombolysis restored patency and achieved similar valvular competence. Surgical thrombectomy, however, resulted in more residual thrombus and contributed to changes in endothelium-mediated relaxations at 4 weeks. Thrombolysis maintained both structural integrity and endothelial function.
Collapse
Affiliation(s)
- J M Rhodes
- Division of Vascular Surgery, Department of Surgery, Mayo Clinic and Foundation, Rochester, MN 55905, USA
| | | | | | | | | | | |
Collapse
|
49
|
Miller VM, Rud KS, Gloviczki P. Pharmacological assessment of adrenergic receptors in human varicose veins. INT ANGIOL 2000; 19:176-83. [PMID: 10905803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Experiments were to characterize pharmacologically adrenergic receptors in human varicose veins to the natural transmitter norepinephrine and to an extract of Ruscus. METHODS Greater saphenous veins and varicose tributaries from patients undergoing elective surgery for primary varicose disease and portions of greater saphenous veins from patients undergoing peripheral arterial reconstruction (control) were suspended for the measurement of isometric force in organ chambers. Concentration response curves were obtained to norepinephrine or the extract of Ruscus aculeatus in the absence and presence of selective antagonists of alpha, and alpha2 adrenergic receptors. RESULTS Norepinephrine and Ruscus extract caused concentration-dependent contractions in all veins. Contractions to norepinephrine were greater in control veins than in varicose tributaries. Contractions to the extract were greater in varicose tributaries than in greater saphenous veins from varicose patients. Contractions to norepinephrine were reduced similarly by alpha and alpha2-adrenergic agonists in control and varicose veins but to a greater extent by alpha2-blockade in greater saphenous veins from varicose patients. Contractions to Ruscus extract were not reduced by alpha-adrenergic blockade in control veins but were reduced by alpha2-adrenergic blockade in varicose veins. CONCLUSIONS These results suggest a differential distribution of alpha adrenergic receptors on greater saphenous veins from non-varicose patients compared to those with primary varicose disease. Venotropic agents from plant extract probably exert effects by way of multiple receptor and non-receptor mediated events.
Collapse
Affiliation(s)
- V M Miller
- Department of Surgery, Mayo Clinic and Foundation, Rochester, MN 55905, USA.
| | | | | |
Collapse
|
50
|
Abstract
Experiments were designed to determine mechanisms by which Dendroaspis natriuretic peptide (DNP) causes relaxations in coronary arteries. Rings of canine left circumflex artery with and without endothelium were suspended in organ chambers filled with Krebs-Ringer bicarbonate solution (37 degrees C, bubbled with 95% O2/5% CO2). Concentration-response curves to DNP (10(-10) to 3 x 10(-7) M) were obtained in arteries contracted with prostaglandin (PGF(2alpha), 2 x 10(-6) M), either in the absence or the presence of C-ANP (10(-6) M) to inhibit natriuretic clearance receptors; indomethacin to inhibit cyclooxygenase (INDO, 10(-5) M), N(G)-monomethyl-L-arginine to inhibit production of nitric oxide (L-NMMA; 10(-4) M), HS-142-1 to inhibit particulate guanylate cyclase (10(-5) M); 1H-[1,2,4]oxadiazolo-[4,3-alpha]quinoxalin-1-one to inhibit soluble guanylate cyclase (ODQ; 10(-5) M), or tetraethylammonium to inhibit potassium channels (TEA; 10(-3) or 10(-2) M). Relaxations to DNP were greater in rings with than in those without endothelium. C-ANP significantly attenuated relaxations to DNP only in rings with endothelium. HS-146-1 but not INDO, L-NMMA, ODQ, and TEA significantly reduced relaxations to DNP in rings with and without endothelium contracted with PGF(2alpha). These results suggest that the endothelium augments inhibitory effects of DNP and that natriuretic clearance receptors mediate this component of the response to DNP in canine coronary arteries. In addition, relaxations to DNP in canine arterial smooth muscle involve activation of particulate guanylate cyclase but not hyperpolarization.
Collapse
Affiliation(s)
- E Collins
- Department of Surgery, Physiology, and Biophysics, Mayo Clinic, Rochester, Minnesota 55905, USA
| | | | | | | |
Collapse
|