Baroreceptor Denervation Prevents Sympathoinhibition During Angiotensin II–Induced Hypertension
- 1 July 2005
- journal article
- Published by Ovid Technologies (Wolters Kluwer Health) in Hypertension
- Vol. 46 (1), 168-172
- https://doi.org/10.1161/01.hyp.0000168047.09637.d4
Abstract
Arterial baroreflexes are well established to provide the basis for short-term control of arterial pressure; however, their role in long-term pressure control is more controversial. We proposed that if the sustained decrease in renal sympathetic nerve activity (RSNA) we observed previously in response to angiotensin II-induced hypertension is baroreflex mediated, then the decrease in RSNA in response to angiotensin II would not occur in sinoaortic-denervated (SAD) animals. Arterial pressure and RSNA were recorded continuously via telemetry in sham and SAD rabbits living in their home cages before, during, and after a 7-day infusion of angiotensin II (50 ng . kg(-1) . min(-1)). The arterial pressure responses in the 2 groups of rabbits were not significantly different (82+/-3 mm Hg sham versus 83+/-3 mm Hg SAD before angiotensin II infusion, and 101+/-6 mm Hg sham versus 100+/-4 mm Hg SAD day 6 of angiotensin II). In sham rabbits, there was a significant sustained decrease in RSNA (53+/-7% of baseline on day 2 and 65+/-7% on day 6 of the angiotensin II). On ceasing the angiotensin II, all variables recovered to baseline. In contrast, RSNA did not change in SAD rabbits with the angiotensin II infusion (RSNA was 98+/-8% of baseline on day 2 and 98+/-8% on day 6 of the angiotensin II infusion). These results support our hypothesis that the reduction in RSNA in response to a pressor dose of angiotensin II is dependent on an intact arterial baroreflex pathway.Keywords
This publication has 27 references indexed in Scilit:
- What Sets the Long-Term Level of Renal Sympathetic Nerve ActivityCirculation Research, 2003
- Apoptosis is involved in the cardiac damage induced by sinoaortic denervation in ratsClinical and Experimental Pharmacology and Physiology, 2003
- Unloading arterial baroreceptors causes neurogenic hypertensionAmerican Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2002
- Renal and cardiac sympathetic baroreflexes in hypertensive rabbits.Clinical and Experimental Pharmacology and Physiology, 2001
- LONG‐TERM SYMPATHO‐EXCITATORY EFFECT OF ANGIOTENSIN II: A MECHANISM OF SPONTANEOUS AND RENOVASCULAR HYPERTENSIONClinical and Experimental Pharmacology and Physiology, 1997
- Sympathoneural and haemodynamic characteristics of young subjects with mild essential hypertensionJournal Of Hypertension, 1993
- Indirect evidence for an endothelium-derived contracting factor release in aorta of deoxycorticosterone acetate-salt hypertensive ratsJournal Of Hypertension, 1990
- Angiotensin-induced hypertension in the rat. Sympathetic nerve activity and prostaglandins.Hypertension, 1989
- Elevated sympathetic nerve activity in borderline hypertensive humans. Evidence from direct intraneural recordings.Hypertension, 1989
- Chronic angiotensin II infusion decreases renal norepinephrine overflow in conscious dogs.Hypertension, 1984