| Abstract: | Investigated the proposal that the subfornical organ (SFO) is a site of receptors for drinking induced by angiotensin II (AII). A total of 159 male albino Holtzman rats was used. Intracranial injections of physiological doses of AII elicited drinking if and only if applied directly to the SFO (Exp I). Ablation of the SFO selectively (Exp II) and permanently (Exp IV) eliminated drinking elicited by physiological doses of iv infused AII. Animals in which SFO had been ablated responded normally to cellular dehydration but reduced responding to the extracellular thirsts of beta-adrenergic activation and hyperoncotic colloid dialysis (Exp III). Infusion of saralasin, an AII antagonist, directly into the SFO selectively and reversibly antagonized iv AII drinking (Exp V). The hypothesis that the SFO contains dipsogenic receptors for circulating AII was supported. (2 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
