Long-term Effects of Midazolam, Penehyclidine Hydrochloride on Learning and Memory in Mice / 医学研究杂志

ABSTRACT

Objective To investigate the long-term effects of midazolam and penehyclidine hydrochloride on learning and memory function of mice.Methods According stratified random block design ,80 KM mice were divided into 4 groups midazolam 1mg/kg(group M,n=20), penehyclidine hydrochloride 0.2mg/kg(group P,n=20),midazolam 1mg/kg + penehyclidine hydrochloride 0.2mg/kg(group M+P,n=20) and control group(group NS,n=20);20 mice in each group were divided randomly into testing memory acquisition(n=10) and memory consolidation(n=10) further.For behavioral testing a step-through passive avoidance test was used,in order to evaluate the effects of the agents administruted on the memory acquisition before fraining and on the memory consolidafion immediately after fraining.The step-through latencies and the numbers of errors 1,2,3,4,5,6 and 7 day after the training were recorded.Results Administration of midazolam impaired memory acquisition and consolidation when administrated alone or in combination with penehyclidine hydrochloride, and this effect persisted for 3 days . Administration of midazolam combinated with penehyclidine hydrochloride did not worsen the effect on memory acquisition,but worsen the effect on memory consolidation obviously. Furthermore, administration of midazolam combinated with penehyclidine hydrochloride impaired memory function persisting longer than that of administration of midazolam alone.Conclusions Administration of midazolam and penehyclidine hydrochloride as premedication was advantageous for prevention of awareness during operation, nevertheless was attributed to one of the causations of POCD.