Aim: Our previous study indicated petroleum ether layer of Cnidium monnieri L. Cuss. (CM) and its ingredient osthole could alleviate scopolamine-induced amnesia in female rats.
Materials and methods: Hence, this study was desired to investigate the mechanism of the ameliorating effects of petroleum ether layer of CM on the performance impairment of inhibitory avoidance task and Morris water maze induced by scopolamine in male rats.
Results: CM at 0.1-0.6g/kg orally administered 60 min before the training trial ameliorated the scopolamine-induced performance impairment on inhibitory avoidance learning and water maze in male rats. Only adrenalectomy but not peripheral cholinergic antagonist scopolamine methylbromide and catecholaminergic neurotoxin 6-hydroxydopamine blocked the ameliorating effects of CM on scopolamine-induced performance impairment in rats.
Conclusion: Therefore, we demonstrated that the ameliorating effects of CM on scopolamine-induced performance impairment may be related to activating the adrenal gland and central acetylcholingeric neuron, instead of peripheral nervous system.