Role of brain angiotensin in thirst and sodium appetite of rats.

The role of brain angiotensin II (ANG II) in water, Na and food intake of rats was studied. Intracerebroventricular (i.c.v.) infusion (100 micrograms/h) of the non-peptide ANG II receptor antagonist losartan (type 1), but not PD123319 (type 2), completely blocked water intake caused by i.c.v. infusion of ANG II at 50 ng/h. Following food deprivation, food intake was reduced by PD123319 and associated water intake was decreased by losartan or PD123319. Neither water intake after water deprivation nor Na intake after Na depletion was altered by losartan or PD123319. In conclusion, evidence was consistent with a role for brain ANG II in both food and water intake after food deprivation but not in thirst subsequent to water deprivation or Na intake after Na depletion alone.