Effect of melatonin on behavior of rats of acute sleep deprivation and its working mechanism

    LIU Fangª²E1,LIU Liª²Bing1,CHEN Jianª²Kang1,CHEN Zhiª²Yang1,YANG Fang1,HUA Qianª²Zhen2,QU Ping1

    1Center of Basic Medicine Teaching Experiment, School of Basic Medicine, 2School of Nursing, Fourth Military Medicine University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To explore the effect of melatonin (MT) on the behavior of rats with acute sleep deprivation (SD) and the related bioª²mechanism. METHODS: Twentyª²four Sprague Dawley rats were divided into 3 groups: control group (SD + sodium chloride), experimental group 1 (SD + MT, 5 mg/ kg) and experimental group 2 (SD + MT, 15 mg/ kg). The rats were injected intraperitoneally with MT or sodium chloride one time a day for 1 week. SD was induced in the rats housed on small platform over water. After 72 h SD, the rats¬ð behavior was measured by "open field test" and then malondialdehyde (MDA) and nitric oxide (NO) contents in cerebral cortex and hippocampus of the rats were measured by TBA and Griess method respectively. RESULTS: The excitability and explorative behavior of the 2 experimental groups in the "open field" significantly decreased compared with those of the control group (P<0.05, P<0.01). There was a doseª²effect relationship in the experimental groups. The contents of NO or MDA in cerebral cortex and hippocampus of the experimental groups were lower than those of the control group(P<0.01). CONCLUSION: Melatonin depresses the excitability in the rats of acute sleep deprivation, possibly by inhibiting the increase of NO and MDA in cerebral cortex and hippocampus of the rats. ......