Interaction between Angiotensinergic System and GABAergic System on Thirst in Adult Male Rats

Thirst is a subjective perception that provides the urge for human and animals to drink fluids and it is important for maintaining body fluid homeostasis and may arise from deficits in either intracellular or extracellular fluid volume. Gamma-aminobutyric acid (GABA) and Angiotensin (Ang) receptors in the brain are involved with thirst, water intake and balance of body liquid. The present study investigated the interaction between Angiotensinergic and GABAergic systems on water intake in adult male rats. Intracerebroventricular (i.c.v.) injections were carried out in all experiments after 24 h deprivation of water intake. After deprivation the volume of consumed water was measured for 1 h. Administration of Losartan (45 μg/rat), Muscimol (0.1 μg/rat) significantly decreased water intake while, i.c.v. microinjection of Bicuculline (1 μg/rat) significantly increased it as compared to Saline-treated controls. I.C.V. microinjection of Muscimol 15 min after Losartan administration decreased water intake significantly, while, i.c.v. microinjection of Bicuculline 15min after Losartan administration could attenuate increasing effect of Bicuculline on water intake. It is concluded that Angiotensinergic system have interaction with GABAergic system on water intake.