1
|
Alhummiany B, Sharma K, Buckley DL, Soe KK, Sourbron SP. Physiological confounders of renal blood flow measurement. MAGMA (NEW YORK, N.Y.) 2023:10.1007/s10334-023-01126-7. [PMID: 37971557 DOI: 10.1007/s10334-023-01126-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 09/26/2023] [Accepted: 10/12/2023] [Indexed: 11/19/2023]
Abstract
OBJECTIVES Renal blood flow (RBF) is controlled by a number of physiological factors that can contribute to the variability of its measurement. The purpose of this review is to assess the changes in RBF in response to a wide range of physiological confounders and derive practical recommendations on patient preparation and interpretation of RBF measurements with MRI. METHODS A comprehensive search was conducted to include articles reporting on physiological variations of renal perfusion, blood and/or plasma flow in healthy humans. RESULTS A total of 24 potential confounders were identified from the literature search and categorized into non-modifiable and modifiable factors. The non-modifiable factors include variables related to the demographics of a population (e.g. age, sex, and race) which cannot be manipulated but should be considered when interpreting RBF values between subjects. The modifiable factors include different activities (e.g. food/fluid intake, exercise training and medication use) that can be standardized in the study design. For each of the modifiable factors, evidence-based recommendations are provided to control for them in an RBF-measurement. CONCLUSION Future studies aiming to measure RBF are encouraged to follow a rigorous study design, that takes into account these recommendations for controlling the factors that can influence RBF results.
Collapse
Affiliation(s)
- Bashair Alhummiany
- Department of Biomedical Imaging Sciences, University of Leeds, Leeds, LS2 9NL, UK.
| | - Kanishka Sharma
- Department of Imaging, Infection, Immunity and Cardiovascular Disease, The University of Sheffield, Sheffield, UK
| | - David L Buckley
- Department of Biomedical Imaging Sciences, University of Leeds, Leeds, LS2 9NL, UK
| | - Kywe Kywe Soe
- Department of Imaging, Infection, Immunity and Cardiovascular Disease, The University of Sheffield, Sheffield, UK
| | - Steven P Sourbron
- Department of Imaging, Infection, Immunity and Cardiovascular Disease, The University of Sheffield, Sheffield, UK.
| |
Collapse
|
2
|
Turner CG, Stanhewicz AE, Nielsen KE, Wong BJ. Reply to Letter to the Editor in response to: Microvascular endothelial function following cessation of long-term oral contraceptive pill use. Exp Physiol 2023; 108:1095-1097. [PMID: 37232519 PMCID: PMC10988508 DOI: 10.1113/ep091262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 05/15/2023] [Indexed: 05/27/2023]
Affiliation(s)
- Casey G. Turner
- Department of Kinesiology and HealthGeorgia State UniversityAtlantaGAUSA
- Molecular Cardiology Research InstituteTufts Medical CenterBostonMAUSA
| | - Anna E. Stanhewicz
- Department of Health and Human PhysiologyUniversity of IowaIowa CityIAUSA
| | - Karen E. Nielsen
- Department of Population Health Sciences, School of Public HealthGeorgia State UniversityAtlantaGAUSA
| | - Brett J. Wong
- Department of Kinesiology and HealthGeorgia State UniversityAtlantaGAUSA
| |
Collapse
|
3
|
Turner CG, Stanhewicz AE, Nielsen KE, Otis JS, Feresin RG, Wong BJ. Effects of biological sex and oral contraceptive pill use on cutaneous microvascular endothelial function and nitric oxide-dependent vasodilation in humans. J Appl Physiol (1985) 2023; 134:858-867. [PMID: 36861674 PMCID: PMC10042598 DOI: 10.1152/japplphysiol.00586.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
The purpose of this study was to evaluate in vivo endothelial function and nitric oxide (NO)-dependent vasodilation between women in either menstrual or placebo pill phases of their respective hormonal exposure [either naturally cycling (NC) or using oral contraceptive pills (OCPs)] and men. A planned subgroup analysis was then completed to assess endothelial function and NO-dependent vasodilation between NC women, women using OCP, and men. Endothelium-dependent and NO-dependent vasodilation were assessed in the cutaneous microvasculature using laser-Doppler flowmetry, a rapid local heating protocol (39°C, 0.1 °C/s), and pharmacological perfusion through intradermal microdialysis fibers. Data are represented as means ± standard deviation. Men displayed greater endothelium-dependent vasodilation (plateau, men: 71 ± 16 vs. women: 52 ± 20%CVCmax, P < 0.01), but lower NO-dependent vasodilation (men: 52 ± 11 vs. women: 63 ± 17%NO, P = 0.05) compared with all women. Subgroup analysis revealed NC women had lower endothelium-dependent vasodilation (plateau, NC women: 48 ± 21%CVCmax, P = 0.01) but similar NO-dependent vasodilation (NC women: 52 ± 14%NO, P > 0.99), compared with men. Endothelium-dependent vasodilation did not differ between women using OCP and men (P = 0.12) or NC women (P = 0.64), but NO-dependent vasodilation was significantly greater in women using OCP (74 ± 11%NO) than both NC women and men (P < 0.01 for both). This study highlights the importance of directly quantifying NO-dependent vasodilation in cutaneous microvascular studies. This study also provides important implications for experimental design and data interpretation.NEW & NOTEWORTHY This study supports differences in microvascular endothelial function and nitric oxide (NO)-dependent vasodilation between women in low hormone phases of two hormonal exposures and men. However, when separated into subgroups of hormonal exposure, women during placebo pills of oral contraceptive pill (OCP) use have greater NO-dependent vasodilation than naturally cycling women in their menstrual phase and men. These data improve knowledge of sex differences and the effect of OCP use on microvascular endothelial function.
Collapse
Affiliation(s)
- Casey G Turner
- Department of Kinesiology and Health, Georgia State University, Atlanta, Georgia, United States
| | - Anna E Stanhewicz
- Department of Health and Human Physiology, University of Iowa, Iowa City, Iowa, United States
| | - Karen E Nielsen
- Department of Population Health Sciences, School of Public Health, Georgia State University, Atlanta, Georgia, United States
| | - Jeffrey S Otis
- Department of Kinesiology and Health, Georgia State University, Atlanta, Georgia, United States
| | - Rafaela G Feresin
- Department of Nutrition, Georgia State University, Atlanta, Georgia, United States
| | - Brett J Wong
- Department of Kinesiology and Health, Georgia State University, Atlanta, Georgia, United States
| |
Collapse
|
4
|
Quinn KM, Roberts L, Cox AJ, Borg DN, Pennell EN, McKeating DR, Fisher JJ, Perkins AV, Minahan C. Blood oxidative stress biomarkers in women: influence of oral contraception, exercise, and N-acetylcysteine. Eur J Appl Physiol 2022; 122:1949-1964. [PMID: 35674828 PMCID: PMC9287208 DOI: 10.1007/s00421-022-04964-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 04/29/2022] [Indexed: 11/30/2022]
Abstract
Purpose To compare physiological responses to submaximal cycling and sprint cycling performance in women using oral contraceptives (WomenOC) and naturally cycling women (WomenNC) and to determine whether N-acetylcysteine (NAC) supplementation mediates these responses. Methods Twenty recreationally trained women completed five exercise trials (i.e., an incremental cycling test, a familiarisation trial, a baseline performance trial and two double-blind crossover intervention trials). During the intervention trials participants supplemented with NAC or a placebo 1 h before exercise. Cardiopulmonary parameters and blood biochemistry were assessed during 40 min of fixed-intensity cycling at 105% of gas-exchange threshold and after 1-km cycling time-trial. Results WomenOC had higher ventilation (β [95% CI] = 0.07 L·min−1 [0.01, 0.14]), malondialdehydes (β = 12.00 mmol·L−1 [6.82, 17.17]) and C-reactive protein (1.53 mg·L−1 [0.76, 2.30]), whereas glutathione peroxidase was lower (β = 22.62 mU·mL−1 [− 41.32, − 3.91]) compared to WomenNC during fixed-intensity cycling. Plasma thiols were higher at all timepoints after NAC ingestion compared to placebo, irrespective of group (all p < 0.001; d = 1.45 to 2.34). For WomenNC but not WomenOC, the exercise-induced increase in malondialdehyde observed in the placebo trial was blunted after NAC ingestion, with lower values at 40 min (p = 0.018; d = 0.73). NAC did not affect cycling time-trial performance. Conclusions Blood biomarkers relating to oxidative stress and inflammation are elevated in WomenOC during exercise. There may be an increased strain on the endogenous antioxidant system during exercise, since NAC supplementation in WomenOC did not dampen the exercise-induced increase in malondialdehyde. Future investigations should explore the impact of elevated oxidative stress on exercise adaptations or recovery from exercise in WomenOC. Supplementary Information The online version contains supplementary material available at 10.1007/s00421-022-04964-w.
Collapse
Affiliation(s)
- Karlee M Quinn
- Griffith Sports Science, Griffith University, Gold Coast, QLD, 4222, Australia. .,Sport Performance Innovation and Knowledge Excellence Unit, Queensland Academy of Sport, Nathan, QLD, 4111, Australia.
| | - Llion Roberts
- Griffith Sports Science, Griffith University, Gold Coast, QLD, 4222, Australia.,Sport Performance Innovation and Knowledge Excellence Unit, Queensland Academy of Sport, Nathan, QLD, 4111, Australia.,School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Amanda J Cox
- School of Medical Science, Griffith University, Gold Coast, QLD, 4222, Australia.,Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, 4222, Australia
| | - David N Borg
- The Hopkins Centre, Menzies Health Institute Queensland, Griffith University, Brisbane, QLD, 4102, Australia
| | - Evan N Pennell
- School of Medical Science, Griffith University, Gold Coast, QLD, 4222, Australia
| | - Daniel R McKeating
- School of Medical Science, Griffith University, Gold Coast, QLD, 4222, Australia
| | - Joshua J Fisher
- School of Medical Science, Griffith University, Gold Coast, QLD, 4222, Australia
| | - Anthony V Perkins
- School of Medical Science, Griffith University, Gold Coast, QLD, 4222, Australia
| | - Clare Minahan
- Griffith Sports Science, Griffith University, Gold Coast, QLD, 4222, Australia
| |
Collapse
|
5
|
Dos Santos PA, de Oliveira AM, Alves CQ, Souza Filho CF, Ladeia AMT, Petto J. Renin-Angiotensin-Aldosterone System in Women Using Combined Oral Contraceptive: A Systematic Review. REVISTA BRASILEIRA DE GINECOLOGIA E OBSTETRICIA : REVISTA DA FEDERACAO BRASILEIRA DAS SOCIEDADES DE GINECOLOGIA E OBSTETRICIA 2022; 44:710-718. [PMID: 35724684 PMCID: PMC9948294 DOI: 10.1055/s-0042-1745790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To describe the effects of combined oral contraceptives (COC) on the renin-angiotensin-aldosterone system (RAAS). DATA SOURCES This is a systematic review according to the criteria of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), registered in PROSPERO under the ID: CRD42020200019. Searches were performed between August 2020 and December 2021, in the following databases: Medline via Pubmed, Cochrane Central Library, Scientific Electronic Library Online, and Latin American and Caribbean Literature in Health Sciences via Virtual Health Library. The effects of the combined oral contraceptive on plasma renin activity values, plasma renin values, angiotensinogen values- also known as plasma renin substrate- angiotensin, and/or aldosterone values. STUDY SELECTION A total of 877 studies were selected and, of these, 10 articles met the eligibility criteria and were included in this review. DATA COLLECTION Data were combined through qualitative synthesis and included in a spreadsheet previously prepared by the authors. DATA SYNTHESIS The collected samples ranged from 18 to 137 participants, totaling 501 women aged between 18 and 49 years throughout all studies. The studies showed increased activity of plasma renin, plasma renin substrate, angiotensin II, and aldosterone in this population. CONCLUSION The findings of this study suggest that the COC promotes greater activation of the RAAS. Supporting the idea that its use is related to an increased risk of cardiovascular events, including systemic arterial hypertension.
Collapse
Affiliation(s)
| | | | | | | | | | - Jefferson Petto
- Escola Bahiana de Medicina e Saúde Pública, Salvador, BA, Brazil.,Actus Cordios Reabilitação Cardiovascular, Respiratória e Metabólica, Salvador, BA, Brazil.,Centro Universitário UniFTC, Salvador, BA, Brazil
| |
Collapse
|
6
|
Nicholl DDM, Hanly PJ, Zalucky AA, Handley GB, Sola DY, Ahmed SB. Nocturnal hypoxemia severity influences the effect of CPAP therapy on renal renin-angiotensin-aldosterone system activity in humans with obstructive sleep apnea. Sleep 2021; 44:5983782. [PMID: 33734385 DOI: 10.1093/sleep/zsaa228] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/09/2020] [Indexed: 01/12/2023] Open
Abstract
STUDY OBJECTIVES Nocturnal hypoxemia (NH) in obstructive sleep apnea (OSA) is associated with renal renin-angiotensin-aldosterone system (RAAS) up-regulation and loss of kidney function. Continuous positive airway pressure (CPAP) therapy is associated with RAAS down-regulation, though the impact of NH severity remains unknown. We sought to determine whether NH severity alters the effect of CPAP on renal hemodynamics and RAAS activity in humans. METHODS Thirty sodium-replete, otherwise healthy, OSA participants (oxygen desaturation index ≥ 15 h-1) with NH (SpO2 < 90% ≥ 12%/night) were studied pre- and post-CPAP (>4 h/night∙4 weeks). NH severity was characterized as moderate (mean SpO2[MSpO2] ≥ 90%; N = 15) or severe (MSpO2 < 90%; N = 15). Glomerular filtration rate (GFR), renal plasma flow (RPF), and filtration fraction (FF) were measured at baseline and in response to angiotensin-II (3 ng/kg/min∙30 min, 6 ng/kg/min∙30 min), a marker of RAAS activity. RESULTS Pre-CPAP, baseline renal hemodynamics did not differ by NH severity. Pre-CPAP, severe NH participants demonstrated blunted GFR (Δ30 min, -9 ± 4 vs 1 ± 3 mL/min, p = 0.021; Δ60 min, -5 ± 5 vs 8 ± 5 mL/min, p = 0.017) and RPF (Δ30 min, -165 ± 13 vs -93 ± 19 mL/min, p = 0.003; Δ60 min, -208 ± 18 vs -112 ± 22 mL/min, p = 0.001; moderate vs severe) responses to angiotensin-II. Post-CPAP, severe NH participants demonstrated maintained GFR (112 ± 5 vs 108 ± 3 mL/min, p = 0.9), increased RPF (664 ± 35 vs 745 ± 34 mL/min, p = 0.009), reduced FF (17.6 ± 1.4 vs 14.9 ± 0.6%, p = 0.009), and augmented RPF responses to Angiotensin-II (Δ30 min, -93 ± 19 vs -138 ± 16 mL/min, p = 0.009; Δ60 min, -112 ± 22 vs -175 ± 20 mL/min, p = 0.001; pre- vs post-CPAP), while moderate participants were unchanged. CONCLUSIONS Correction of severe, but not moderate, NH with CPAP therapy was associated with improved renal hemodynamics and decreased renal RAAS activity in humans with OSA.
Collapse
Affiliation(s)
- David D M Nicholl
- Department of Medicine, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Patrick J Hanly
- Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Sleep Centre, Foothills Medical Centre, Calgary, AB, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Ann A Zalucky
- Department of Medicine, University of Toronto, Toronto, ON, Canada
| | | | - Darlene Y Sola
- Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Sofia B Ahmed
- Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute, University of Calgary, Calgary, AB, Canada.,Alberta Kidney Disease Network, AB, Canada
| |
Collapse
|
7
|
Wickham KA, McCarthy DG, Pereira JM, Cervone DT, Verdijk LB, van Loon LJC, Power GA, Spriet LL. No effect of beetroot juice supplementation on exercise economy and performance in recreationally active females despite increased torque production. Physiol Rep 2020; 7:e13982. [PMID: 30653856 PMCID: PMC6336290 DOI: 10.14814/phy2.13982] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 12/18/2018] [Indexed: 01/06/2023] Open
Abstract
This study investigated the effects of acute and chronic beetroot juice (BRJ) supplementation on submaximal exercise oxygen uptake (VO2), time trial (TT) performance, and contractile properties of the plantar flexors in females. Study 1: Using a double blind, randomized, crossover design, 12 recreationally active females using hormonal contraceptives supplemented acutely (2.5 h) and chronically (8 days) with 280 mL BRJ/d (~26 mmoles nitrate [NO3−]) or a NO3−‐free placebo (PLA). On days 1 and 8, participants cycled for 10 min at 50% and 70% VO2peak and completed a 4 kJ/kg body mass TT. Plasma [NO3−] and nitrite ([NO2−]) increased significantly following BRJ supplementation versus PLA. There was no effect of BRJ supplementation on VO2 at 50% or 70% VO2peak, or TT performance. Study 2: 12 recreationally active females (n = 7 from Study 1) using hormonal contraceptives participated in a baseline visit and were supplemented acutely (2.5 h) and chronically (8 days) with 280 mL BRJ/d. Maximum voluntary strength (MVC) of the plantar flexors was assessed and a torque‐frequency curve performed. BRJ had no effect on MVC, voluntary activation, peak twitch torque, time to peak torque, or half relaxation time. Following both acute (46.6 ± 4.9% of 100 Hz torque) and chronic (47.2 ± 4.4%) supplementation, 10 Hz torque was significantly greater compared to baseline (32.9 ± 2.6%). In summary, BRJ may not be an effective ergogenic aid in recreationally active females as it did not reduce submaximal exercise VO2 or improve aerobic TT performance despite increasing low frequency torque production.
Collapse
Affiliation(s)
- Kate A Wickham
- Department of Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Devin G McCarthy
- Department of Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Jamie M Pereira
- Department of Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Daniel T Cervone
- Department of Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Lex B Verdijk
- Department of Human Biology, Maastricht University, Maastricht, The Netherlands
| | - Luc J C van Loon
- Department of Human Biology, Maastricht University, Maastricht, The Netherlands
| | - Geoffrey A Power
- Department of Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| | - Lawrence L Spriet
- Department of Human Health and Nutritional Sciences, University of Guelph, Ontario, Canada
| |
Collapse
|
8
|
Response of women using oral contraception to exercise in the heat. Eur J Appl Physiol 2017; 117:1383-1391. [PMID: 28477076 DOI: 10.1007/s00421-017-3628-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 04/28/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE To compare the response of long-term oral contraceptive users (WomenOC; n = 8) to naturally menstruating women (WomenNM; n = 8) at rest and during exercise in temperate (TEMP; 22 °C) and hot (HEAT; 35 °C) conditions. METHODS Participants performed a three-stage cycling trial in each condition at 90, 135, and 180% of lactate threshold 1 (total = 52.5 min). Heart rate (HR) and core temperature (T c) were recorded continuously, whereas blood pressure (BP), ratings of perceived exertion (RPE), blood lactate [La-], and skin blood flow (BFsk) were recorded every 7.5 min. RESULTS Baseline T c was higher in WomenOC (37.5 ± 0.2, 37.6 ± 0.3 °C) than WomenNM (37.2 ± 0.2, 37.0 ± 0.4 °C) before the TEMP (p = 0.03) and HEAT (p < 0.01) trials, respectively. This difference remained for 22.5 min into both trials (p ≤ 0.05), after which time no between-group differences were found (p > 0.05). BFsk measured in WomenNM plateaued from 7.5 min in the HEAT, whereas BFsk measured in WomenOC increased for 15.0 min (p = 0.02) before plateauing. There were no between-group differences in HR, BP, or blood [La-] before or throughout either trial (p > 0.05). WomenOC had higher (p ≤ 0.04) RPE values than WomenNM in the HEAT, reporting 8 ± 1 and 6 ± 2 at the end of Stage 3, respectively. CONCLUSIONS WomenOC concluded both trials with a comparable T c to WomenNM, but had a prolonged BFsk response and elevated RPE in the HEAT. Changes to BFsk and RPE observed in women using OC may have implications for exercise tolerance in hot conditions.
Collapse
|
9
|
Limberg JK, Peltonen GL, Johansson RE, Harrell JW, Kellawan JM, Eldridge MW, Sebranek JJ, Walker BJ, Schrage WG. Greater Beta-Adrenergic Receptor Mediated Vasodilation in Women Using Oral Contraceptives. Front Physiol 2016; 7:215. [PMID: 27375493 PMCID: PMC4896959 DOI: 10.3389/fphys.2016.00215] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/23/2016] [Indexed: 11/25/2022] Open
Abstract
Background: β-adrenergic receptors play an important role in mitigating the pressor effects of sympathetic nervous system activity in young women. Based on recent data showing oral contraceptive use in women abolishes the relationship between muscle sympathetic nervous system activity and blood pressure, we hypothesized forearm blood flow responses to a β-adrenergic receptor agonist would be greater in young women currently using oral contraceptives (OC+, n = 13) when compared to those not using oral contraceptives (OC–, n = 10). Methods: Women (18–35 years) were studied during the early follicular phase of the menstrual cycle (days 1–5) or placebo phase of oral contraceptive use. Forearm blood flow (FBF, Doppler ultrasound) and mean arterial blood pressure (MAP, brachial arterial catheter) were measured at baseline and during graded brachial artery infusion of the β-adrenergic receptor agonist, Isoproterenol (ISO), as well as Acetylcholine (ACH, endothelium-dependent vasodilation) and Nitroprusside (NTP, endothelium-independent vasodilation). Forearm vascular conductance was calculated (FVC = FBF/MAP, ml/min/100 mmHg) and the rise in FVC from baseline during infusion quantified vasodilation (ΔFVC = FVCinfusion − FVCbaseline). Results: ISO increased FVC in both groups (p < 0.01) and ISO-mediated ΔFVC was greater in OC+ compared to OC– (Main effect of group, p = 0.02). Expressing data as FVC and FBF resulted in similar conclusions. FVC responses to both ACH and NTP were also greater in OC+ compared to OC–. Conclusions: These data are the first to demonstrate greater β-adrenergic receptor-mediated vasodilation in the forearm of women currently using oral contraceptives (placebo phase) when compared to those not using oral contraceptives (early follicular phase), and suggest oral contraceptive use influences neurovascular control.
Collapse
Affiliation(s)
| | | | | | - John W Harrell
- Department of Kinesiology, University of Wisconsin Madison, WI, USA
| | | | - Marlowe W Eldridge
- Department of Kinesiology, University of WisconsinMadison, WI, USA; Department of Pediatrics, University of WisconsinMadison, WI, USA
| | - Joshua J Sebranek
- Department of Anesthesiology, University of Wisconsin Madison, WI, USA
| | - Benjamin J Walker
- Department of Anesthesiology, University of Wisconsin Madison, WI, USA
| | | |
Collapse
|
10
|
Ahmed SB, Ramesh S. Sex hormones in women with kidney disease. Nephrol Dial Transplant 2016; 31:1787-1795. [DOI: 10.1093/ndt/gfw084] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 03/19/2016] [Indexed: 12/21/2022] Open
|
11
|
Harvey RE, Hart EC, Charkoudian N, Curry TB, Carter JR, Fu Q, Minson CT, Joyner MJ, Barnes JN. Oral Contraceptive Use, Muscle Sympathetic Nerve Activity, and Systemic Hemodynamics in Young Women. Hypertension 2015; 66:590-7. [PMID: 26101348 PMCID: PMC4537364 DOI: 10.1161/hypertensionaha.115.05179] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 05/28/2015] [Indexed: 01/21/2023]
Abstract
Endogenous female sex hormones influence muscle sympathetic nerve activity (MSNA), a regulator of arterial blood pressure and important factor in hypertension development. Although ≈80% of American women report using hormonal contraceptives sometime during their life, the influence of combined oral contraceptives (OCs) on MSNA and systemic hemodynamics remains equivocal. The goal of this study was to determine whether women taking OCs have altered MSNA and hemodynamics (cardiac output and total peripheral resistance) at rest during the placebo phase of OC use compared with women with natural menstrual cycles during the early follicular phase. We retrospectively analyzed data from studies in which healthy, premenopausal women (aged 18-35 years) participated. We collected MSNA values at rest and hemodynamic measurements in women taking OCs (n=53; 25±4 years) and women with natural menstrual cycles (n=74; 25±4 years). Blood pressure was higher in women taking OCs versus those with natural menstrual cycles (mean arterial pressure, 89±1 versus 85±1 mm Hg, respectively; P=0.01), although MSNA was similar in both groups (MSNA burst incidence, 16±1 versus 18±1 bursts/100 heartbeats, respectively; P=0.19). In a subset of women in which detailed hemodynamic data were available, those taking OCs (n=33) had similar cardiac output (4.9±0.2 versus 4.7±0.2 L/min, respectively; P=0.47) and total peripheral resistance (19.2±0.8 versus 20.0±0.9 U, respectively; P=0.51) as women with natural menstrual cycles (n=22). In conclusion, women taking OCs have higher resting blood pressure and similar MSNA and hemodynamics during the placebo phase of OC use when compared with naturally menstruating women in the early follicular phase.
Collapse
Affiliation(s)
- Ronee E Harvey
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.).
| | - Emma C Hart
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| | - Nisha Charkoudian
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| | - Timothy B Curry
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| | - Jason R Carter
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| | - Qi Fu
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| | - Christopher T Minson
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| | - Michael J Joyner
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| | - Jill N Barnes
- From the Department of Anesthesiology, Mayo Clinic, Rochester, MN (R.E.H., T.B.C., M.J.J., J.N.B.); School of Physiology and Pharmacology, University of Bristol, Bristol, United Kingdom (E.C.H.); Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA (N.C.); Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton (J.R.C.); Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center (Q.F.); and Department of Human Physiology, University of Oregon, Eugene (C.T.M.)
| |
Collapse
|
12
|
Wu Q, Lai X, Zhu Z, Hong Z, Dong X, Wang T, Wang H, Lou Z, Lin Q, Guo Z, Chai Y. Evidence for Chronic Kidney Disease-Mineral and Bone Disorder Associated With Metabolic Pathway Changes. Medicine (Baltimore) 2015; 94:e1273. [PMID: 26266360 PMCID: PMC4616673 DOI: 10.1097/md.0000000000001273] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Abnormalities in the levels of calcium, phosphorus, and parathyroid hormone (PTH) in serum are typical for patients with chronic kidney disease (CKD). They are used routinely to predict the onset of CKD-mineral and bone disorder (MBD). However, CKD-MBD associated with metabolic pathway imbalance is not well understood.The objective of the study was to identify endogenous metabolic signatures in patients with intact PTH using mass spectrometry-based metabolomics. This study was a cross-sectional study. Ultra performance liquid chromatography-Quadrupole Time-of-Flight/mass spectrometry-based metabolic profiling was employed to analyze serum samples from 19 disease controls (DCs) (intact parathyroid hormone [iPTH] 150-300 pg/mL) and 19 secondary hyperparathyroidism (SHPT) patients (iPTH >300 pg/mL) (the training data set) to identify metabolic biomarkers for CKD-MBD. Then, another set of samples including 19 DCs (iPTH 150-300 pg/mL) and 19 SHPT patients (iPTH >300 pg/mL) (the test data set) were used to validate the potential biomarkers identified.Metabolic profiling analyses revealed different patterns of endogenous metabolites between the SHPT and the DC groups. A total of 32 unique metabolites were identified and 30 metabolites were elevated in the iPTH compared with control serum pools. Cytidine and L-phenylalanine were downregulated in the SHPT patients. The metabolic signatures identified were assessed respectively by an internal 10-fold cross validation with an accuracy of 91.4% and an external validation with an accuracy of 71.1%, a sensitivity of 73.7%, and a specificity of 68.4%.Mass spectrometry-based metabolomic analyses for SHPT patients promises immense potential for early diagnosis and therapy monitoring. Our results indicated that the onset of CKD-MBD is associated with pathway changes of protein synthesis and metabolism, amino acid metabolism, energy metabolism, and steroid hormone metabolism, with obvious promise for better understanding the pathogenesis of this disease. Several metabolic biomarkers were identified, which warrant further development.
Collapse
Affiliation(s)
- Qiong Wu
- From the School of Pharmacy (QW, ZZ, ZH, XD, ZL, YC); Department of Nephrology (XL, TW, HW, ZG), Changhai Hospital, Second Military Medical University, Shanghai, China; and Proteomics/Mass Spectrometry Facility (QL), Center for Functional Genomics, University at Albany, Rensselaer, NY
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Zaltzman JS, Lai V, Schulz MZ, Moon KH, Cherney DZ. A randomized cross-over comparison of short-term exposure of once-daily extended release tacrolimus and twice-daily tacrolimus on renal function in healthy volunteers. Transpl Int 2014; 27:1294-302. [PMID: 25160518 PMCID: PMC4497360 DOI: 10.1111/tri.12435] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 07/13/2014] [Accepted: 08/20/2014] [Indexed: 11/26/2022]
Abstract
Calcineurin inhibitor nephrotoxicity remains an issue for transplant recipients. The pharmacokinetic profile (PK) of the once-daily tacrolimus extended release (Tac-ER) includes equivalent exposure [AUC(0-24 h) ] but lower Cmax versus twice-daily tacrolimus immediate release (Tac-IR). We hypothesized that the unique PK profiles would result in pharmacodynamic differences in renal function. Nineteen healthy male subjects were allocated to once-daily Tac-ER and twice-daily Tac-IR in a prospective, randomized, two period, cross-over study. Tacrolimus was titrated to achieve trough levels of 8-12 ng/ml. Twenty four hours ERPF and GFR estimated by para-aminohippurate and sinistrin clearance were performed at baseline and at the end of each 10-day dosing period. Mean Tac C0 was 11.0 ± 2.2 and 11.3 ± 1.8 ng/ml for Tac-ER and Tac-IR, respectively. The mean Effective 24 h renal plasma flow (ERPF) was significantly higher with Tac-ER compared with Tac-IR (658 ± 127 vs. 610 ± 93 ml/min/1.73 m(2) , P = 0.046). There was a trend to a greater mean GFR over 24 h for Tac-ER at 114.5 ± 13.6 ml/min/1.73 m(2) compared with 108.9 ± 9.7 ml/min/1.73 m(2) for Tac-IR, P = 0.116. Under controlled physiological conditions, ERPF was significantly improved with Tac-ER compared with Tac-IR, likely owing to the differing PKs of these tacrolimus preparations (ClinicalTrials.gov Identifier: NCT01681134).
Collapse
Affiliation(s)
- Jeffrey S Zaltzman
- Renal Transplant Program, Department of Medicine, Li Ka Shing Institute St. Michael's University of Toronto, Toronto, ON, Canada
| | | | | | | | | |
Collapse
|
14
|
Boldo A, White WB. Blood pressure effects of the oral contraceptive and postmenopausal hormone therapies. Endocrinol Metab Clin North Am 2011; 40:419-32, ix. [PMID: 21565676 DOI: 10.1016/j.ecl.2011.01.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Oral contraceptives and postmenopausal hormone therapy may induce hypertension through multiple mechanisms, including sodium and volume retention. Numerous studies have shown significant increases in blood pressure (BP) with the chronic administration of oral contraceptives as well as reversibility with discontinuation. The effects of different classes of oral contraceptive agents and hormonal replacement therapy on BP and associated effects on other cardiovascular risk factors are covered in this article. Novel hormonal replacement therapy that lowers BP is also discussed.
Collapse
Affiliation(s)
- Angela Boldo
- Division of Endocrinology, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA
| | | |
Collapse
|
15
|
Cherney DZI, Sochett EB, Lai V, Dekker MG, Slorach C, Scholey JW, Bradley TJ. Renal hyperfiltration and arterial stiffness in humans with uncomplicated type 1 diabetes. Diabetes Care 2010; 33:2068-70. [PMID: 20585001 PMCID: PMC2928365 DOI: 10.2337/dc10-0767] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE We have reported that renal hyperfiltration is associated with endothelial dysfunction in early type 1 diabetes. However, the relationship between renal hyperfiltration and arterial stiffness is unknown. Accordingly, we measured arterial stiffness in type 1 diabetic subjects with hyperfiltering (n = 20) or normofiltering (n = 18). RESEARCH DESIGN AND METHODS Augmentation index (AIx), aortic pulse wave velocity (PWV), renal hemodynamic function (inulin and paraaminohippurate clearances), and urinary and circulating plasma cGMP were measured in normoalbuminuric subjects with type 1 diabetes during clamped euglycemia (glucose 4-6 mmol/l) and hyperglycemia (glucose 9-11 mmol/l). RESULTS During clamped euglycemia, hyperfiltering subjects (glomerular filtration rate >or=135 ml/min/1.73 m(2)) exhibited lower AIx values (-6.1 +/- 2.9 vs. 13.9 +/- 2.7%, P = 0.001) and higher cGMP levels in urine and plasma compared with normofiltering subjects. These differences were maintained during clamped hyperglycemia. As expected, renal hemodynamic responses to clamped hyperglycemia were exaggerated in normofilterers, but values for AIx remained unchanged. CONCLUSIONS Renal hyperfiltration is associated with reduced arterial stiffness in subjects with uncomplicated type 1 diabetes.
Collapse
Affiliation(s)
- David Z I Cherney
- Toronto General Hospital, Division of Nephrology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
| | | | | | | | | | | | | |
Collapse
|
16
|
Endothelial-mediated microcirculatory responses to an acute estradiol test are influenced by time since menopause, cumulative hormone exposure, and vasomotor symptoms. Menopause 2010; 17:749-57. [DOI: 10.1097/gme.0b013e3181cde2bd] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
17
|
Sarna MA, Hollenberg NK, Seely EW, Ahmed SB. Oral contraceptive progestins and angiotensin-dependent control of the renal circulation in humans. J Hum Hypertens 2009; 23:407-14. [PMID: 19158821 PMCID: PMC3712637 DOI: 10.1038/jhh.2008.148] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Oral contraceptive (OC) use is associated with increased intra-renal renin-angiotensin-aldosterone system (RAA System) activity and risk of nephropathy, though the contribution of progestins contained in the OC in the regulation of angiotensin-dependent control of the renal circulation has not been elucidated. Eighteen OC users (8 non-diabetic, 10 Type 1 diabetic) were studied in high salt balance, a state of maximal RAA System suppression. Progestational and androgenic activity of the progestin in each OC was standardized to that of the reference progestin norethindrone. Renal plasma flow (RPF) was measured by paraaminohippurate clearance at baseline and in response to angiotensin converting enzyme (ACE)-inhibition. There was a positive correlation between OC progestational activity and the RPF response to ACE-inhibition (r=0.52, p=0.03). Similar results were noted with OC androgenic activity (r=0.54, p=0.02). On subgroup analysis, only non-diabetic subjects showed an association between progestational activity and angiotensin-dependent control of the renal circulation (r=0.71, p=0.05 non-diabetic; r=0.14, p=0.7 diabetic; p=0.07 between groups). Similar results were noted with respect to androgenic activity (r=0.88, p=0.005 non-diabetic; r=−0.33, p=0.3 diabetic; p=0.002 between groups). Our results suggest that the OC progestin component is a significant influence on the degree of angiotensin-dependent control of the renal circulation, though these findings may not apply to women with diabetes.
Collapse
Affiliation(s)
- M A Sarna
- Department of Medicine, University of Calgary, Alberta, Canada
| | | | | | | |
Collapse
|
18
|
Endothelial nitric oxide synthase gene polymorphisms and the renal hemodynamic response to L-arginine. Kidney Int 2008; 75:327-32. [PMID: 19037250 DOI: 10.1038/ki.2008.574] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Nitric oxide is generated from L-arginine by nitric oxide synthase (NOS), an enzyme that exists in several isoforms. Some studies found that a polymorphism (G894T) in the endothelial NOS gene was associated with decreased nitric oxide bioactivity and vascular complications. However, it is not known whether the enzyme had a reduced activity. Here we measured the effect of an infusion of L-arginine on renal hemodynamic function in subjects segregated by the presence or absence of the T allele. If this polymorphism represented a functional variant, subjects with the GT/TT form should exhibit a blunted renal hemodynamic response to L-arginine compared to those with a GG allele. All subjects were given a diet controlled for sodium and protein intake. GG subjects had lower mean arterial pressure and an augmented glomerular filtration rate at baseline. In response to a graded L-arginine infusion, this group had significant changes in effective renal plasma flow, glomerular filtration rate, filtration fraction, renal vascular resistance, and renal blood flow. The renal response to L-arginine in GT/TT subjects was blunted. Circulating cGMP levels and endothelial NOS mRNA expression, measured in skin biopsies by real-time PCR, did not differ between the groups. Our study shows that the G894T allele of endothelial NOS is associated with a blunted response to L-arginine, suggesting this polymorphism may be a functional variant in humans.
Collapse
|
19
|
|
20
|
Lee J. Nitric oxide in the kidney : its physiological role and pathophysiological implications. Electrolyte Blood Press 2008; 6:27-34. [PMID: 24459519 PMCID: PMC3894485 DOI: 10.5049/ebp.2008.6.1.27] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Accepted: 02/01/2008] [Indexed: 12/02/2022] Open
Abstract
Nitric oxide has been implicated in many physiologic processes that influence both acute and long-term control of kidney function. Its net effect in the kidney is to promote natriuresis and diuresis, contributing to adaptation to variations of dietary salt intake and maintenance of normal blood pressure. A pretreatment with nitric oxide donors or L-arginine may prevent the ischemic acute renal injury. In chronic kidney diseases, the systolic blood pressure is correlated with the plasma level of asymmetric dimethylarginine, an endogenous inhibitor of nitric oxide synthase. A reduced production and biological action of nitric oxide is associated with an elevation of arterial pressure, and conversely, an exaggerated activity may represent a compensatory mechanism to mitigate the hypertension.
Collapse
Affiliation(s)
- Jongun Lee
- Department of Physiology, Chonnam National University Medical School, Gwangju, Korea
| |
Collapse
|