LESIONS OF THE ORGANUM VASCULOSUM OF THE LAMINA TERMINALIS (OVLT) ATTENUATE OSMOTICALLY-INDUCED DRINKING AND VASOPRESSIN SECRETION IN THE DOG

Abstract

Drinking and secretion of arginine vasopressin (AVP) in response to intravenous infusion of hypertonic NaCl were studied in dogs before and after destruction of the OVLT. The functional relationship between plasma osmolality and plasma AVP was eliminated following destruction of the OVLT. Furthermore, osmotically-induced drinking was significantly reduced in dogs with OVLT lesions. These data are compatible with the hypothesis that the OVLT contains osmoreceptors in the dog.