Sex Differences in Vascular Responses to Exercise

Sex Differences in the Renal Vascular Responses of AT1 and Mas Receptors in Two-Kidney-One-Clip Hypertension

International Journal of Hypertension ◽

10.1155/2021/8820646 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Zahra Pezeshki ◽

Mehdi Nematbakhsh

Keyword(s):

Sex Differences ◽

Female Rats ◽

Receptor Interaction ◽

Ang Ii ◽

Male And Female ◽

Vascular Responses ◽

Mas Receptor ◽

Male And Female Rats ◽

Renal Vascular ◽

The Impact

Background. The prevalence and severity of hypertension, as well as the activity of the systemic and local renin angiotensin systems (RASs), are gender related, with more symptoms in males than in females. However, the underlying mechanisms are not well understood. In this study, we investigated sex differences in renal vascular responses to angiotensin II (Ang II) administration with and without Ang II type 1 and Mas receptor (AT1R and MasR) antagonists (losartan and A779) in the 2K1C rat model of renovascular hypertension. Methods. Male and female 2K1C rats were divided into 8 experimental groups (4 of each sex) treated with vehicle, losartan, A779, or A779+losartan. Responses of mean arterial pressure (MAP), renal blood flow (RBF), and renal vascular resistance (RVR) to Ang II were determined. Results. In both sexes, the basal MAP, RBF, and RVR were not significantly different between the four groups during the control period. The Ang II administration decreased RBF and increased RVR in a dose-related manner in both sexes pretreated with vehicle or A779 ( P dose < 0.0001 ), but in vehicle pretreated groups, RBF and RVR responses were different between male and female rats ( P group < 0.05 ). AT1R blockade increased RBF and decreased RVR responses to Ang II, and no difference between the sexes was detected. Coblockades of AT1R and MasR receptors increased RBF response to Ang II significantly in males alone but not in females ( P group = 0.04 ). Conclusion. The impact of Ang II on RBF and RVR responses seems to be gender related with a greater effect on males, and this sex difference abolishes by Mas receptor blockade. However, the paradoxical role of dual losartan and A779 may provide the different receptor interaction in RAS between male and female rats.

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Lack of limb or sex differences in the cutaneous vascular responses to exogenous norepinephrine

Journal of Applied Physiology ◽

10.1152/japplphysiol.00575.2014 ◽

2014 ◽

Vol 117 (12) ◽

pp. 1417-1423 ◽

Cited By ~ 15

Author(s):

Jody L. Greaney ◽

Anna E. Stanhewicz ◽

W. Larry Kenney ◽

Lacy M. Alexander

Keyword(s):

Sex Differences ◽

Receptor Antagonist ◽

Young Women ◽

Adrenergic Receptor ◽

Receptor Blockade ◽

Doppler Flowmetry ◽

Vascular Responses ◽

Cutaneous Vasodilation ◽

Vascular Responsiveness ◽

Cutaneous Vasoconstriction

The cutaneous circulation is used to examine vascular adrenergic function in clinical populations; however, limited studies have examined whether there are regional limb and sex differences in microvascular adrenergic responsiveness. We hypothesized that cutaneous adrenergic responsiveness would be greater in the leg compared with the arm and that these regional limb differences would be blunted in young women ( protocol 1). We further hypothesized that cutaneous vasoconstriction to exogenous norepinephrine (NE) during β-adrenergic receptor antagonism would be augmented in young women ( protocol 2). In protocol 1, one microdialysis fiber was placed in the skin of the calf and the ventral forearm in 20 healthy young adults (11 men and 9 women). Laser-Doppler flowmetry was used to measure red blood cell flux in response to graded intradermal microdialysis infusions of NE (10−12 to 10−2 M). In protocol 2, three microdialysis fibers were placed in the forearm (6 men and 8 women) for the local perfusion of lactated Ringer (control), 5 mM yohimbine (α-adrenergic receptor antagonist), or 2 mM propranolol (β-adrenergic receptor antagonist) during concurrent infusions of NE (10−12 to 10−2 M). There were no limb or sex differences in cutaneous adrenergic responsiveness (logEC50) to exogenous NE. During α-adrenergic receptor blockade, women had greater exogenous NE-induced cutaneous vasodilation at the lowest doses of NE (10−12 to 10−10 M). Collectively, these data indicate that there are no limb or sex differences in cutaneous adrenergic responsiveness to exogenous NE; however, young women have a greater β-adrenergic receptor-mediated component of the vascular responsiveness to exogenous NE.

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Similar Effects of Acute Resistance Exercise on Carotid Stiffness in Males and Females

International Journal of Sports Medicine ◽

10.1055/a-1044-2321 ◽

2020 ◽

Vol 41 (02) ◽

pp. 82-88

Author(s):

Georgios Grigoriadis ◽

Alexander J. Rosenberg ◽

Wesley K. Lefferts ◽

Sang Ouk Wee ◽

Elizabeth C Schroeder ◽

...

Keyword(s):

Blood Pressure ◽

Sex Differences ◽

Elastic Modulus ◽

Resistance Exercise ◽

Aortic Stiffness ◽

Arterial Compliance ◽

Post Exercise ◽

Vascular Responses ◽

Carotid Stiffness ◽

Males And Females

AbstractSex differences exist in vascular responses to blood pressure perturbations, such as resistance exercise. Increases in aortic stiffness following acute resistance exercise appear different between sexes, with attenuated increases in females vs. males. Whether sex differences exist in carotid stiffness, following resistance exercise is unknown. This study sought to examine sex differences in carotid stiffness, aortic stiffness, and hemodynamics following acute resistance exercise. Thirty-five participants (18 male) completed 3 sets of 10 repetitions of maximal isokinetic knee extension/flexion. Aortic stiffness and hemodynamics were estimated using an automated oscillometric blood pressure monitor at baseline, 5- and 30-min post-exercise. Carotid stiffness was assessed by β-stiffness index, pressure-strain elastic modulus and arterial compliance using ultrasonography. Resistance exercise increased aortic stiffness, mean and systolic pressure at 5-min (p<0.01), and pressure-strain elastic modulus at 5-min in both sexes (p<0.05). Arterial compliance decreased at 5- and 30-min post exercise in both sexes (p<0.01). No interaction effects were detected in carotid stiffness, aortic stiffness, and hemodynamics, indicating similar vascular responses between sexes. Our findings indicate that the large arteries appear to stiffen similarly following resistance exercise in males and females when presented with similar blood pressure responses.

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Sex differences in mesenteric endothelial function of streptozotocin-induced diabetic rats: a shift in the relative importance of EDRFs

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00327.2012 ◽

2012 ◽

Vol 303 (10) ◽

pp. H1183-H1198 ◽

Cited By ~ 27

Author(s):

Rui Zhang ◽

Der Thor ◽

Xiaoyuan Han ◽

Leigh Anderson ◽

Roshanak Rahimian

Keyword(s):

Sex Differences ◽

Vascular Reactivity ◽

Barium Chloride ◽

Diabetic Rats ◽

Mesenteric Arteries ◽

Female Rat ◽

Relative Importance ◽

Atpase Inhibitor ◽

Male And Female ◽

Vascular Responses

Several studies suggest that diabetes affects male and female vascular beds differently. However, the mechanisms underlying the interaction of sex and diabetes remain to be investigated. This study investigates whether there are 1) sex differences in the development of abnormal vascular responses and 2) changes in the relative contributions of endothelium-derived relaxing factors in modulating vascular reactivity of mesenteric arteries taken from streptozotocin (STZ)-induced diabetic rats at early and intermediate stages of the disease (1 and 8 wk, respectively). We also investigated the mesenteric expression of the mRNAs for endothelial nitric oxide (NO) synthase (eNOS) and NADPH oxidase (Nox) in STZ-induced diabetes in both sexes. Vascular responses to acetylcholine (ACh) in mesenteric arterial rings precontracted with phenylephrine were measured before and after pretreatment with indomethacin (cyclooxygenase inhibitor), Nω-nitro-l-arginine methyl ester (NOS inhibitor), or barium chloride (Kir blocker) plus ouabain (Na+-K+-ATPase inhibitor). We demonstrated that ACh-induced relaxations were significantly impaired in mesenteric arteries from both male and female diabetic rats at 1 and 8 wk. However, at 8 wk the extent of impairment was significantly greater in diabetic females than diabetic males. Our data also showed that in females, the levels of eNOS, Nox2, and Nox4 mRNA expression and the relative importance of NO to the regulation of vascular reactivity were substantially enhanced, whereas the importance of endothelium-derived hyperpolarizing factor (EDHF) was significantly reduced at both 1 and 8 wk after the induction of diabetes. This study reveals the predisposition of female rat mesenteric arteries to vascular injury after the induction of diabetes may be due to a shift away from a putative EDHF, initially the major vasodilatory factor, toward a greater reliance on NO.

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