- 作者: R.K.W. Chan; Y.S. Chan; T.M. Wong
- 作者服務機構: Department of Physiology, Faculty of Medicine, The University of Hong Kong, Hong Kong
- 中文摘要: --
- 英文摘要: The interactive role of rostral ventrolateral medulla (RVL) cardiovascular neurons and brain angiotensin II (Ang II) in regulating the arterial blood pressure was examined by recording simultaneously the spontaneous activity of these spinal projecting neurons and the arterial blood pressure in the pentobarbital-anesthetized spontaneously hypertensive rat (SHR) and its normotensive control, the Wistar Kyoto rat (WKY). It was found that Ang II elicited dose-dependent excitatory responses in a subpopulation of RVL cardiovascular neurons, followed by a subsequent increase in blood pressure. These effects of Ang II were significantly greater in SHR than in WKY. The effects were attenuated or abolished by co-administration of Ang II antagonist, [Sar1, Ile8]-Ang II. Pre-administration of [Sar1, Ile8]-Ang II to RVL using bilateral microinjection attenuated the blood pressure effects of intracerebroventricularly administered Ang II by as much as 70%. These results indicated that spinal projecting RVL cardiovascular neurons are important in mediating the pressor action of Ang II. The enhanced sensitivity and responsiveness of RVL cardiovascular neurons to Ang II may be pertinent to the genesis of hypertension in adult SHR.
- 中文關鍵字: --
- 英文關鍵字: Rostral ventrolateral medulla ; Cardiovascular neurons ; Arterial blood pressure ; Angiotensin II ; Hypertension