ANGIOTENSIN-II AND ITS 3-7 FRAGMENT IMPROVE RECOGNITION BUT NOT SPATIAL MEMORY IN RATS

The effects of angiotensin II (AII), its 3-7 fragment [AII(3-7)] and t he substituted 3-7 fragment [Leu-5,AII(3-7)] given intracerebroventric ularly (ICV) at the dose of 1 nmole each, on spatial memory and recogn ition were tested. AII(3-7) increased while Leu-5,AII(3-7) slightly de creased session to session foot shock reinforced runtime to the goal i n a complex 6 chamber maze. The animals treated with AII performed in the maze similarly to saline injected controls. Overall number of erro rs was unchanged in all peptide treated groups in comparison with the control group. Object recognition was significantly improved in all th e peptide treated groups except for the Leu-5,AII(3-7) group. The resu lts point to the facilitation of recognition and lack of influence on, or even attenuation of, spatial memory by AII and its 3-7 fragment. L eu-5,AII(3-7) caused similar though less pronounced effects.