Inhibitory effect of atriopeptinergic neurons in AV3V region on angiotensinII pressor system in rat brain.
In the central nervous system and the periphery, atrial natriuretic peptide (ANP) and angiotensinII(AngII) play important and opposite roles in regulating blood pressure and fluid electrolyte balance. Their central mechanisms are unclear. In the brain the anteroventral third ventricle region (AV3V) contains the most prominent collection of atriopeptin-like immunoreactive perikarya. Our previous studies show that: (1) AV3V stimulation by glutamate produces a fall in blood pressure; (2) there is an AngII pressor system composed of the lateral hypothalamus/perifornical region (LH/PF), subfornical organ (SFO), nucleus paraventricularis (NPV) and rostral ventrolateral medulla (RVL). The present study was to examine whether ANPergic projections from the AV3V could act on nuclei involved in the above-mentioned AngII pressor system. Here we demonstrate that: (1) Injection of atriopeptinIII into the LH/PF, SFO, NPV, or RVL induces a depressor response; whereas injection of normal saline has no effect. (2) Pre-injection of A 71915 (an atriopeptinIII antagonist) into the LH/PF, SFO, NPV, or RVL reverses the depressor response of the AV3V to glutamate (Glu). The results suggest that excitation of atriopeptinergic neurons in the AV3V by Glu produces an inhibitory effect on each nucleus in the LH/PF-SFO-NPV-RVL AngII pressor system.
Ku
Yun-Hui
YH
Department of Physiology, Peking University Health Science Center, Beijing 100083, PR China. yunhui_ku@163.com
Li
Yao-Hua
YH
D000804:Angiotensin II / Q000378:metabolism; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects*; D001921:Brain / Q000502:physiology*; D006339:Heart Rate / Q000187:drug effects*; D008297:Male; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012970:Sodium Glutamate / Q000008:administration & dosage*
D000804:Angiotensin II; D009320:Atrial Natriuretic Factor; D012970:Sodium Glutamate