Pharmacol Res. 2001 Jan; 43(1): 17-22.

The ameliorating effect of the water layer of Fructus Schisandrae on cycloheximide-induced amnesia in rats: interaction with drugs acting at neurotransmitter receptors.

Hsieh MT, Wu CR, Wang WH, Lin LW.

Institute of Chinese Pharmaceutical Sciences, China Medical College, 91 Hsueh Shih Road, Taichung, Taiwan, 40421, Republic of China. [email protected]

Our previous study indicated that the water layer present in Fructus Schisandra(FS(w)) at 10 and 25 mg kg(-1)significantly counteracted cycloheximide (CXM)-induced amnesia. Therefore, the mechanism of action of the ameliorating effect of FS(w)on CXM-induced amnesia in the passive avoidance task was investigated in rats. The ameliorating effect of FS(w)on CXM-induced amnesia was depressed by scopolamine. The serotonin releaser, p -chloroamphetamine significantly antagonized the ameliorating effect of FS(w)on CXM-induced amnesia. Furthermore, the ameliorating effect was also inhibited by the 5-HT(1A)receptor agonist 8-OH-DPAT, but potentiated by the 5-HT(2)receptor antagonist ritanserin. Finally, the GABA(A)receptor antagonist bicuculline blocked the ameliorating effect of FS(w). These results suggest that the beneficial effect of FS(w)on CXM-induced amnesia is amplified by treatment with serotonergic 5-HT(2)receptor antagonists, but reduced by serotonergic 5-HT(1A)receptor agonists as well as GABA(A)and cholinergic receptor antagonists.Copyright 2001 Academic Press.