Sympathetic and angiotensin-dependent hypertension during cage-switch stress in mice
Open Access
- 1 December 2004
- journal article
- Published by American Physiological Society in American Journal of Physiology-Regulatory, Integrative and Comparative Physiology
- Vol. 287 (6), R1394-R1398
- https://doi.org/10.1152/ajpregu.00306.2004
Abstract
The goal of this study was to determine the dependence of the acute hypertensive response to a novel model of acute psychosocial stress on the sympathetic and renin-angiotensin systems. Baseline mean arterial pressure (MAP), heart rate (HR), and locomotor activity were measured with telemetry in mice for a 1-h period and averaged 98 ± 1 mmHg, 505 ± 3 beats/min, and 5 ± 1 counts, respectively. Stress was induced by placing a mouse into a cage previously occupied by a different male mouse, and this increased MAP, HR, and activity in the control group by 40 ± 2 mmHg, 204 ± 25 beats/min, and 68 ± 6 counts, respectively. Each variable gradually returned to baseline levels by 90 min after beginning cage switch. Pretreatment with terazosin (10 mg/kg ip) significantly reduced the initial increase in MAP to 12 ± 6 mmHg, whereas MAP for the last 45 min was superimposable on control values. Atenolol (10 mg/ml drinking water) had no effect to blunt the initial increase in MAP but had a growing effect from 10 min onward, decreasing MAP all the way to baseline by 60 min after starting cage switch. Captopril (2 mg/ml drinking water) treatment caused a very similar response. All three treatments significantly decreased the area under the blood pressure curve, and the blood pressure effect could not be attributed uniformly to effects on HR or activity. These data suggest that our novel model of psychosocial stress causes an initial α1-receptor-dependent increase in MAP. The later phase of the pressor response is blocked similarly by a β1-receptor antagonist and an ACE inhibitor, independent of HR, suggesting that the β1-dependent blood pressure effect is due, in large part, to the renin-angiotensin system.Keywords
This publication has 18 references indexed in Scilit:
- Stress, inflammation and cardiovascular diseaseJournal of Psychosomatic Research, 2002
- Autonomic cardiovascular control in conscious miceAmerican Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2000
- Nervous KidneyHypertension, 2000
- ROLE OF CARDIOVASCULAR REACTIVITY TO MENTAL STRESS IN PREDICTING FUTURE HYPERTENSIONClinical and Experimental Hypertension, 2000
- Neural mechanisms in primary hypertension Efficacy of α-blockade with doxazosin during stressAmerican Journal of Hypertension, 1996
- The central role of corticotrophin‐releasing factor (CRF‐41) in psychological stress in rats.The Journal of Physiology, 1993
- Lewis K. Dahl Memorial Lecture. The renin system and four lines fo hypertension research. Nephron heterogeneity, the calcium connection, the prorenin vasodilator limb, and plasma renin and heart attack.Hypertension, 1992
- Local hormonal factors (intracrine, autocrine, and paracrine) in hypertension.Hypertension, 1991
- Sympathetic modulation of renal hemodynamics, renin release and sodium excretionKlinische Wochenschrift, 1989
- Vagal and sympathetic components of the heart rate range and gain of the baroreceptor-heart rate reflex in conscious ratsJournal of the Autonomic Nervous System, 1987