Impact of conflict psychological stress on rats'sleep time and sleep phrase / 中华行为医学与脑科学杂志

ABSTRACT

ObjectiveTo discuss the impact of conflict psychological stress on rats'sleep time and sleep phrase.Methods20 Wistar male rats were randomly divided into vehicle group and model group,10 in each group.The improved experiment of Vogel drinking water conflict was used to establish the model of conflict psychological stress in rats and monitoring the changes of rats'weight and concentration of corticosterone (CORT) in serum after a week.After one week,the 12 h EEG and EMG of rats were traced by the polygraph in order to clarify the effect of conflict psychological stress on rats′ sleep time and sleep phrase.ResultsAfter one week,compared with vehicle group the weight of model group decreased significantly ( t =2.87,P ＜ 0.05 ),the concentration of CORT in serum raised significantly( t=5.19,P ＜ 0.05 ).A week later,compared the vehicle group,total sleep time( TST),light sleep,slow wave sleep(SWS) and rapid eye movement sleep (REM) time in model group rats ( (337.8 ±84.2)min,( 169 ±49.2) min,( 136.9 ±40.8)min,(33.1 ± 10.1 ) min for vehicle group; ( 155.4 ±16.7 ) min,( 111.6 ± 16.4 ) min,( 30.6 ± 4.9 ) min,( 12.6 ± 3.3 ) min for model group) were significantly reduced ( t =6.75,2.43,5.51,5.78,P ＜ 0.05 ),and the proportion of lightsleep increased ( (49.6 ± 3.4 ) ％,( 71.7 ±5.4)％ ) ( t =6.90,P＜0.05),the proportion of SWS decreased( (40.3 ± 10.9)％,( 19.8 ±3.2)％ ) ( t=6.74,P ＜ 0.05 ) ;but no significant change in the proportion of REM ( t =1.57,P＞ 0.05 ).Rats,sleep-wake rhythm figure indicated that the rats'sleep duration reduced and the number of awakening increased ; sleep tended to be fragmentation.ConclusionsConflict psychological stress lead to hypothalamus-pituitary-adrenal axis hyperactivity,weight loss,and the rhythm of sleep and sleep phase change in rats.