Comparison of Changes in Blood Pressure and Dipsogenic Responsiveness to Angiotensin II in Male and Female Rats Chronically Exposed to Cold

1996 ◽  
Vol 60 (6) ◽  
pp. 1543-1549 ◽  
Author(s):  
ZHONGJIE SUN ◽  
MELVIN J FREGLY ◽  
NEIL E ROWLAND ◽  
J.ROBERT CADE
Keyword(s):  
Blood Pressure ◽  
Angiotensin Ii ◽  
Female Rats ◽  
Male And Female ◽  
Male And Female Rats

scholarly journals The Preventive Effects of Diminazene Aceturate in Renal Ischemia/Reperfusion Injury in Male and Female Rats

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Maryam Malek ◽  
Mehdi Nematbakhsh
Keyword(s):  
Angiotensin Ii ◽  
Angiotensin Converting Enzyme ◽  
Ischemia Reperfusion ◽  
Renal Ischemia ◽  
Female Rats ◽  
Male Rats ◽  
Converting Enzyme ◽  
Diminazene Aceturate ◽  
Male And Female ◽  
Male And Female Rats

Background. Angiotensin-converting enzyme 2/angiotensin (1-7)/Mas receptor (ACE2/Ang-1-7/MasR) appears to counteract most of the deleterious actions of angiotensin-converting enzyme/angiotensin II/angiotensin II receptor 1 (ACE/Ang II/AT1R) in renal ischemia/reperfusion (I/R) injury but ACE2 activity and its levels are sexually dimorphic in the kidney. This study was designed to evaluate the effects of activation endogenous ACE2 using the diminazene aceturate (DIZE) in renal I/R injury in male and female rats.Methods. 36 Wistar rats were divided into two groups of male and female and each group distinct to three subgroups (n=6). I/R group was subjected to 45 min of bilateral ischemia and 24 h of reperfusion, while treatment group received DIZE (15 mg/kg/day) for three days before the induction of I/R. The other group was assigned as the sham-operated group.Results. DIZE treatment in male rats caused a significant decrease in blood urea nitrogen (BUN), creatinine, liver functional indices, serum malondialdehyde (MDA), and increase kidney nitrite levels (P<0.05), and in female rats a significant increase in creatinine and decrease serum nitrite levels compared to the I/R group (P<0.05).Conclusions. DIZE may protect the male kidney from renal I/RI through antioxidant activity and elevation of circulating nitrite level.

Abstract 9: Endothelin B Receptors Protect Against Hypertension Induced by Chronic Angiotensin II in Female Rats

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Wararat Kittikulsuth ◽  
David M Pollock
Keyword(s):  
Blood Pressure ◽  
High Salt ◽  
Female Rats ◽  
Male Rats ◽  
Ang Ii ◽  
Hypertensive Rats ◽  
High Salt Diet ◽  
Male And Female ◽  
Male And Female Rats ◽  
Endothelin B

Endothelin B (ET B ) receptors mediate vasodilation, anti-inflammation and natriuresis, which ultimately contribute to blood pressure control. We previously showed that renal medullary ET B receptor function is maintained in female angiotensin (Ang) II hypertensive rats, while male Ang II hypertensive rats have blunted ET B -induced natriuretic responses. Because female rats are more resistance to blood pressure elevation induced by high salt intake and/or Ang II infusion, we hypothesized that ET B receptors protect female rats against the hypertensive response and renal injury induced by a high salt diet and chronic Ang II infusion compared to males. Male and female rats received Ang II infusion (150 ng/kg/min; sc.) with 4% NaCl for 4 weeks; blood pressure was measured by telemetry. After a week of Ang II infusion with a high salt diet, subsets of both male and female rats received the ET B antagonist, A-192621, at three doses on consecutive weeks (1, 3, and 10 mg/kg/d in food). Male rats had a significantly higher blood pressure compared to females after 4 weeks of Ang II (178±10 vs. 138±10 mmHg; p<0.05). A-192621 resulted in a dose-dependent increase in blood pressure in female Ang II hypertensive rats (167±8 mmHg at 10 mg/kg/d; p<0.05); the increase produced by A-192621 in male Ang II hypertensive rats was not statistically significant (193±10 mmHg). After 4 weeks of Ang II infusion, the level of proteinuria and nephrinuria was higher in male rats compared to female. A-192621 did not further increase urinary excretion of protein or nephrin in both male and female Ang II hypertensive rats. In conclusion, these results support the hypothesis that ET B receptors provide more protection against hypertension during chronic Ang II infusion in female rats compared to male.

scholarly journals Fetal Undernutrition Induces Resistance Artery Remodeling and Stiffness in Male and Female Rats Independent of Hypertension

Biomedicines ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 424
Author(s):  
Perla Y. Gutiérrez-Arzapalo ◽  
Pilar Rodríguez-Rodríguez ◽  
David Ramiro-Cortijo ◽  
Marta Gil-Ortega ◽  
Beatriz Somoza ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Level ◽  
Female Rats ◽  
Resistance Artery ◽  
Male And Female ◽  
Maternal Undernutrition ◽  
Male And Female Rats ◽  
Males And Females ◽  
Artery Remodeling ◽  
Tail Cuff

Fetal undernutrition programs hypertension and cardiovascular diseases, and resistance artery remodeling may be a contributing factor. We aimed to assess if fetal undernutrition induces resistance artery remodeling and the relationship with hypertension. Sprague–Dawley dams were fed ad libitum (Control) or with 50% of control intake between days 11 and 21 of gestation (maternal undernutrition, MUN). In six-month-old male and female offspring we assessed blood pressure (anesthetized and tail-cuff); mesenteric resistance artery (MRA) structure and mechanics (pressure myography), cellular and internal elastic lamina (IEL) organization (confocal microscopy) and plasma MMP-2 and MMP-9 activity (zymography). Systolic blood pressure (SBP, tail-cuff) and plasma MMP activity were assessed in 18-month-old rats. At the age of six months MUN males exhibited significantly higher blood pressure (anesthetized or tail-cuff) and plasma MMP-9 activity, while MUN females did not exhibit significant differences, compared to sex-matched controls. MRA from 6-month-old MUN males and females showed a smaller diameter, reduced adventitial, smooth muscle cell density and IEL fenestra area, and a leftward shift of stress-strain curves. At the age of eighteen months SBP and MMP-9 activity were higher in both MUN males and females, compared to sex-matched controls. These data suggest that fetal undernutrition induces MRA inward eutrophic remodeling and stiffness in both sexes, independent of blood pressure level. Resistance artery structural and mechanical alterations can participate in the development of hypertension in aged females and may contribute to adverse cardiovascular events associated with low birth weight in both sexes.

Relationship among hyperinsulinemia, insulin resistance, and hypertension is dependent on sex

2002 ◽  
Vol 283 (2) ◽  
pp. H562-H567 ◽  
Author(s):  
Denise M. Galipeau ◽  
Linfu Yao ◽  
John H. McNeill
Keyword(s):  
Insulin Resistance ◽  
Blood Pressure ◽  
Insulin Sensitivity ◽  
Insulin Treatment ◽  
Tolerance Test ◽  
Female Rats ◽  
Male Rats ◽  
Oral Glucose ◽  
Male And Female ◽  
Male And Female Rats

Hyperinsulinemia and insulin resistance have been linked to hypertension; however, the influence of sex on this relationship has not been well studied. The purpose of this experiment was to compare the effects of chronic insulin treatment on insulin sensitivity and blood pressure in male and female rats. Male and female Wistar rats were treated with insulin (2 U/day) via subcutaneous sustained release implants for 5 wk. Systolic blood pressure was measured via the tail-cuff method before and after treatment, and insulin sensitivity was assessed with an oral glucose tolerance test. The insulin sensitivity of female rats was 4.5-fold greater than male rats. Chronic insulin treatment impaired insulin sensitivity in both sexes; however, this occurred to a greater degree in male rats. Blood pressure increased in male rats treated with insulin only. The results demonstrate that hyperinsulinemia and insulin resistance are associated with hypertension in male rats only. Therefore, the link between these conditions appears to depend on sex.

scholarly journals Impact of gonadectomy on blood pressure regulation in ageing male and female rats

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Wioletta Pijacka ◽  
Bethan Clifford ◽  
Dawid Walas ◽  
Chantal Tilburgs ◽  
Jaap A. Joles ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Regulation ◽  
Female Rats ◽  
Pressure Regulation ◽  
Male And Female ◽  
Male And Female Rats ◽  
Ageing Male

A comparison of the dipsogenic responses of male and female rats to a variety of stimuli

1980 ◽  
Vol 58 (10) ◽  
pp. 1180-1183 ◽  
Author(s):  
Susan Kaufman
Keyword(s):  
Polyethylene Glycol ◽  
Angiotensin Ii ◽  
Water Deprivation ◽  
Sexual Difference ◽  
Female Rats ◽  
Male Rats ◽  
Male And Female ◽  
Fluid Compartment ◽  
Male And Female Rats ◽  
Extracellular Stimuli

Female rats subjected to 48 h of water deprivation drank more than similarly deprived males. There was no sexual difference in the dipsogenic responses to intracellular dehydration produced by intravenous hypertonic NaCl but females drank considerably more than males in response to the extracellular stimuli of hyperoncotic polyethylene glycol and angiotensin II. It is concluded that intact adult female rats are dipsogenically more responsive than adult male rats to stimuli acting through the pathways of extracellularly induced thirst but not to those arising from the intracellular fluid compartment.

scholarly journals Sex differences and central protective effect of 17β-estradiol in the development of aldosterone/NaCl-induced hypertension

2009 ◽  
Vol 296 (5) ◽  
pp. H1577-H1585 ◽  
Author(s):  
Baojian Xue ◽  
Daniel Badaue-Passos ◽  
Fang Guo ◽  
Celso E. Gomez-Sanchez ◽  
Meredith Hay ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Protective Effect ◽  
Protective Role ◽  
Female Rats ◽  
Sympathetic Outflow ◽  
Male And Female ◽  
Male And Female Rats ◽  
Induced Hypertension ◽  
Combined Administration ◽  
17Β Estradiol

The present study tested the hypotheses that male and female rats respond differently to subcutaneous infusions of aldosterone (Aldo; 1.8 μg·kg−1·h−1, 1% NaCl to drink; 28 days) and that central estrogen plays a protective role against the development of hypertension. In rats with blood pressure (BP) and heart rate (HR) measured by Data Sciences International telemetry, chronic Aldo/NaCl treatment induced a greater increase in BP in males (Δ25.4 ± 2.4 mmHg) than in females (Δ7.1 ± 2.2 mmHg). Gonadectomy augmented Aldo/NaCl-induced hypertension in females (Δ18.2 ± 2.0 mmHg) but had no effect in males (Δ23.1 ± 2.9 mmHg). Immunohistochemistry for Fra-like activity was higher in the paraventricular nucleus of intact males, castrated males, and ovariectomized (OVX) females compared with intact females after 28 days of Aldo/NaCl treatment. In intact males, central 17β-estradiol (E2) inhibited the Aldo/NaCl increase in BP (Δ10.5 ± 0.8) compared with that in central vehicle plus systemic Aldo/NaCl (Δ26.1 ± 2.5 mmHg) rats. Combined administration of E2 and estrogen receptor antagonist ICI182780 (ICI) blocked the protective effect of E2 (Δ23.2 ± 2.4 mmHg). In intact females central, but not peripheral, infusions of ICI augmented the Aldo/NaCl (Δ20.4 ± 1.8 mmHg) BP increase. Finally, ganglionic blockade after Aldo infusions resulted in a smaller reduction in BP in intact females (−23.9 ± 2.5 mmHg) and in central estrogen-treated males (−30.2 ± 1.0 mmHg) compared with other groups (intact males, −39.3 ± 3.4; castrated males, −41.8 ± 1.9; intact males with central E2 + ICI, −42.3 ± 2.1; OVX females, −40.3 ± 3.3; and intact females with central ICI, −39.1 ± 1.3 mmHg). Chronic Aldo infusion produced increases in NaCl intake and decreases in HR that were both similar in all groups. Taken together, the results indicate that central estrogen plays a protective role in the development of Aldo/NaCl-induced hypertension and that this may result from reduced sympathetic outflow.

Adrenal Glands in the Development of Renal Hypertension in Rats

1957 ◽  
Vol 191 (3) ◽  
pp. 542-548 ◽  
Author(s):  
Melvin J. Fregly
Keyword(s):  
Blood Pressure ◽  
Time Course ◽  
Adrenal Glands ◽  
Renal Hypertension ◽  
Female Rats ◽  
Elevated Blood ◽  
Male And Female ◽  
Male And Female Rats ◽  
Experimental Renal Hypertension ◽  
Adrenalectomized Rats

The adrenal glands of the rat do not appear to be necessary for the development of experimental renal hypertension by kidney encapsulation. Male and female rats became hypertensive when both kidneys were encapsulated with latex envelopes whether they were adrenalectomized two weeks prior to or at the time of kidney encapsulation. The type of hypertension produced in adrenalectomized rats did not differ from that of rats with intact adrenals with regard to time course of development of the elevated blood pressure (6–8 weeks), maximal elevation attained (190–220 mm Hg), polydipsia and hypertrophied hearts.

Sexual dimorphism in angiotensin II-induced hypertension and vascular alterations

2005 ◽  
Vol 83 (5) ◽  
pp. 413-422 ◽  
Author(s):  
R Tatchum-Talom ◽  
K M Eyster ◽  
D S Martin
Keyword(s):  
Blood Pressure ◽  
Angiotensin Ii ◽  
Vascular Function ◽  
Vascular Dysfunction ◽  
Female Rats ◽  
Sprague Dawley ◽  
Arterial Blood ◽  
Male And Female Rats ◽  
Sprague Dawley Rats ◽  
Induced Hypertension

Sex differences in the degree of high blood pressure have been described in several forms of experimental animal models of hypertension. However, the influence of sex on angiotensin II-induced hypertension has not been studied. In the present study, we investigated and compared the effects of chronic angiotensin II treatment on blood pressure and vascular function in male and female rats. Chronic treatment with angiotensin II (0.7 mg/kg daily for 10 d) significantly raised arterial blood pressure in male but not female Sprague–Dawley rats; it upregulated the NAD(P)H oxidase gp67 phox subunit in the aorta of male but not female rats; and it exaggerated the vasoconstrictor responses to norepinephrine and serotonin in the mesenteric vascular bed (MVB) of male but not female rats. Vasodilator responses to acetylcholine (ACh) but not papaverine (PPV) or isoprenaline (ISO) were reduced in the MVB of angiotensin II-treated male but not female rats. ACh, but not PPV or ISO dilatory responses were potentiated in the MVB of angiotensin II-treated female rats. The present findings demonstrate that exogenous angiotensin II upregulates aortic NAD(P)H oxidase gp67 phox subunit, and induces hypertension and mesenteric vascular dysfunction only in male rats.Key words: gender, blood pressure, vascular endothelium, angiotensin II hypertension.

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