Effects of Shenwu Capsule on Learning-Memory Ability and Cholinergic System in Model Rats Induced by Scopolamine

OBJECTIVE To investigate the effects of Shenwu capsule (SW),a new Chinese herb combination drug,on learning-memory ability and cholinergic system in model rats induced by scopolamine (Scop).METHODS Wistar rats were randomly divided into normal control group,Scop model group,Donepezil group (positive control drug),low,medium and high doses of SW groups (0.2,0.6 and 1.8 g·kg-1 ).The drugs were intragastrically administered to rats for two weeks.On day 14,after intraperitoneal injection of scopolamine,rats were subjected to Morris water maze and step-down tests.The activity of acetylcholinesterase (AChE) in cerebral cortex was measured by a biochemical method,choline acetyl transferase (ChAT) and M-cholinergic receptors were determined by radioimmunoassay and radio-ligand method,respectively.RESULTS Compared with model group,a significant decrease of swimming time and distance in Morris water maze test was observed in SW groups.SW also increased the latencies and decreased the number of errors in step-down task (P0.05).SW decreased AChE activity in cerebral cortex,and increased ChAT activity and M-cholinergic receptor binding in the hippocampus and cerebral cortex of model rats (P0.05,P0.01).CONCLUSION SW effectively improved learning-memory ability in model rats induced by scopolamine.The mechanism might be related with the enhancement of M-receptors and ChAT and the inhibition of AChE in the brain.