Central injection of galanin inhibits angiotensin II-induced responses in rats

Galanin inhibits electrical activation of angiotensin II-sensitive neurons in the subfornical organ, which is related to angiotensin II-induced drinking behavior and pressor responses. In this study, the authors investigated whether intracerebroventricular injection of galanin in conscious rats inhibits the responses. Water intake following intracerebroventricular injection of angiotensin II at 100 pmol was inhibited significantly by coinjection of galanin at over 25 pmol, although galanin alone did not affect water intake. Furthermore, angiotensin II-induced pressor responses were inhibited significantly by coinjection of galanin at 50 pmol while galanin alone elicited slight pressor responses. These results suggest that galanin inhibits angiotensin II-induced physiological responses.