Different effects of compound 48/80 and histamine on plasma renin activity

The effects of subcutaneous injection of compound 48/80 and histamine on the water intake, plasma renin activity (PRA) and plasma histamine levels were investigated in the rat. The results suggest that compound 48/80 and histamine stimulate water intake by different mechanisms. The compound 48/80-induced water intake seems to be mainly mediated by stimulation of the renin-angiotensin system. On the other hand, the histamine-induced water intake seems to be directly mediated by its action in the brain.