Intracerebroventricular injection of nicotine antagonize the amnestic and hypnotic effect of enflurane in mice

Aim To investigate the relationship between neuronal nicotinic acetylcholine receptor and the amnesia and hypnosis induced by enflurane in mice.Methods Animal models were established by Intraperitoneal injecting of enflurane(2.2 ml·kg-1 and 0.4 ml·kg-1).Artificial cerebrospinal fluid or different dose of nicotine were intracerebroventricular injected,then sleeping time in the analeptic test was recorded;and the step down latency and error times in the step down test;step through latency and error times in the step through test.For the independent activity test,recorded the independent activity times of mice treated with enflurane(0.4 ml·kg-1) in 5 min.Results Compared with control group,intracerebroventricular nicotine decreased sleeping time in the analeptic test,increased step down latency and step through latency in both step down test and step through test.Furthermore,the error times were decreased in both tests.All the outcomes were significant and the influence was dose-dependent.There was no significant difference for the independent activity times of mice treated with 0.4 ml·kg-1 enflurane by ip injection.Conclusion All the evidence suggested that neuronal nicotinic receptor is one of important targets for the hypnotic and amnestic effect of enflurane in mice.