MELANIN CONCENTRATING HORMONE HIPPOCAMPAL NITRIC OXIDE LEVELS AND MEMORY RETENTION

MARIANA VARAS; MARIA E MONZON; MARIELA F. PÉREZ.; SUSANA RUBIALES

PEPTIDES

ELSEVIER SCIENCE INC

Año: 2002 vol. 23 p. 2213 - 2213

0196-9781

he present study attempts to determine, if the effect of melanin-concentrating hormone (MCH) upon memory retention is correlated with changes in nitric oxide synthase (NOS) activity and tissue levels of nitric oxide (NO) and cGMP. We used a behavioral experiment using a step-down inhibitory avoidance test, the biochemical determinations of NO and cGMP, and electrophysiological model. Results of behavioral studies (step-down test) showed that MCH administration reverts the amnesic effects induced by N(G)-nitro-L-arginine (L-NOArg). Moreover, electrophysiological studies demonstrated that L-NOArg did not block the potentiation induced by the peptide. Hippocampal NO and cGMP levels increased after MCH injection.