Effects of benzodiazepine receptor ligands on the performance of an operant delayed matching to position task in rats: opposite effects of FG 7142 and lorazepam

摘要: The effects of a series benzodiazepine (BZ) receptor ligands, ranging from full agonist through to partial inverse agonists, were examined on short term working memory in the rat. behavioural paradigm used was discrete trial, operant delayed matching position task, as originally described by Dunnett (1985), with delays 0, 5, 15 and 30 s. (BZR) lorazepam (0.25, 0.375 0.5 mg/kg) dose delay dependently impaired accuracy. Lorazepam also increased latency respond decreased number nose pokes made into food tray during delays. In contrast, BZR ZK 95 962 (1, 3, 10 did not affect accuracy, but increase speed responding. antagonist 93 426 (1.25, 25 had no this paradigm. weak agonists Ro 15-4513 (0.1, 1 90 886 3 accuracy performance. However, both these drugs poke responses. These motoric particularly strong following mg/kg 15-4513. This shows that responding can be dissociated. FG 7142 dependent upon dose. lowest (1 significantly improved whereas highest (10 impairment induced accompanied an decrease pokes. Taken together, results show performance modulated opposite ways low agonist, 7142.