Abstract：OBJECTIVE: This study examined the effects of compound ketamine oral solution (CKOS ) on the expression of NMDAR_1 and GABA_AR mRNA in the CA1 and CA3 regions of the hippocampus in rats in order to investigate the mechanism of sedation for this medicine. METHODS: Fifty Spragus- Dawley rats were randomly assigned into ten groups according to the observed time after CKOS administration (0, 5, 10, 15, 30, 60, 90, 120, 240 and 360 minutes, n=5 each). The 0 minute group(Control group) received normal saline instead. Immune histochemistry staining and in situ hybridization were used to determine the expression and the distribution of NMDAR_1 and GABA_AR mRNA in the CA1 and CA3 regions of the hippocampus in various groups. RESULTS: The expressions of GABA_AR mRNA in the CA1 and CA3 regions of hippocampus were gradually increased after CKOS administration, with a significantly higher levels compared with those in the Control group at 30 and 90 minutes after administration. At 360 minutes the expression resumed to the similar levels to the Control group. The expressions of NMDAR_1 in the CA1 and CA3 regions of hippocampus were inhibited after CKOS administration, and were significantly lower compared with those in the Control group at each observed time point. CONCLUSIONS: CKOS may increase the GABA_AR mRNA expression and inhibit the NMDAR_1 expression in the CA1 and CA3 regions of the hippocampus in rats, which may be the underlying mechanism of sedation for this medicine.
ZHANG Jin,CHEN Hua,WANG Wei et al. Effects of compound ketamine oral solution on the expression of NMDA receptor 1 and GABAA receptor mRNA in CA1 and CA3 regions of hippocampus in rats[J]. CJCP, 2005, 7(4): 345-348.
