l-NAME differential effects on diazepam and flunitrazepam responses of rats in the object recognition test

Abstract

Background: The present study was undertaken to better understand possible interaction(s) between a non-selective nitric oxide inhibitor: N(G)-nitro-l-arginine methyl ester (l-NAME) and benzodiazepines (BZs) in recognition memory.

Methods: The study was carried out on adult male albino Wistar rats. A novel object recognition (NOR) task was used to evaluate memory process.

Results: Combined administration of l-NAME (50mg/kg, ip) with a threshold dose of DZ (0.25mg/kg) induced amnesic effects in rats, participating in the NOR test. On the other hand, following a combined administration of l-NAME (100mg/kg, ip) with flunitrazepam (FNZ; 0.1mg/kg), it was found out that l-NAME inhibited the amnesic effects of FNZ on rats in the NOR test.

Conclusions: The obtained results suggest that suppressed NO synthesis may lead to a facilitation of DZ-induced memory impairment but surprisingly may prevent amnesic effect after FNZ in rats, submitted to NOR task.

Keywords: Diazepam; Flunitrazepam; Rat; Recognition memory; l-NAME.