加味天王补心丹对模拟高原暴露模型大鼠睡眠的改善作用及其机制OA北大核心CSTPCD

OBJECTIVE To investigate the effect of Jiawei Tianwang Buxin Dan(JWBXD)on insomnia in rats exposed to simulated high-altitude conditions.METHODS ① Thirty SD rats were randomly divided into the normal control,model,model+Jiawei Tianwang Buxin Dan(JWBXD,9.6 mg·kg-1),model+Tianwang Buxin Dan(TWBXD,9.6 mg·kg-1),and model+diazepam(DZP,3 mg·kg-1)groups.Rats,except for the normal control group,were subjected to a low-pressure,low-oxygen animal experimental chamber simulating a 5000 m altitude.Respective drugs were ig administrated once daily at 9:00 for seven days,and signal acquisition and sleep analysis were conducted by a wireless physiological sig-nal telemetry system.②Forty rats were randomly divided into five groups as described in ①.Through-out the experiment,the general condition and body mass of the rats were observed daily.Drug adminis-tration lasted for seven days,and grip strength was tested one hour after the final administration.ELISA was used to measure the levels of corticotropin-releasing hormone(CRH),adrenocorticotropic hor-mone(ACTH),corticosterone(CORT),and melatonin(MLT)in serum.Western blotting was performed to measure the expression levels of core clock proteins period circadian regulator 2(Per2),circadian locomotor output cycles(Clock),cryptochrome 2(Cry2),brain-muscle arnt-like protein 1(Bmal1),nuclear receptor subfamily 1,group D member 1(NR1D1),glycogen synthase kinase-3β(GSK-3β),as well as acetylserotonin O-methyltransferase(ASMT)in the hypothalamus and pineal gland,respectively.RESULTS ① Compared with the normal control group,the model group exhibited a decrease in total sleep time(P<0.01),an increase in wakefulness(P<0.01),a significant reduction in slow wave sleep(SWS)(P<0.05)and the mean bouts duration(P<0.05).Compared with the model group,both DZP and JWBXD(P<0.01)prolonged sleep time and suppressed wakefulness(P<0.01)in the hypoxic envi-ronment.DZP and JWBXD prolonged SWS(P<0.05,P<0.01),while TWBXD had no significant effect.JWBXD improved the mean bouts duration of SWS in the model rats(P<0.01),whereas no such improvement was observed in model+DZP and model+TWBXD groups.② Compared with the normal control group,the model group showed a significant decrease in forelimb grip strength(P<0.01),increased levels of serum ACTH(P<0.05),CRH,and CORT(P<0.01),and decreased MLT levels(P<0.05).The expression levels of Per2,Cry2,GSK-3β,and NR1D1 in the hypothalamus were downregu-lated(P<0.05,P<0.01),while Bmal1 and Clock were upregulated(P<0.05,P<0.01).ASMT expression in the pineal gland was decreased(P<0.05).Compared with the model group,JWBXD and TWBXD enhanced forelimb grip strength(P<0.01),reduced serum CORT and ACTH levels(P<0.05),decreased CRH levels(P<0.01),and restored MLT levels(P<0.01).JWBXD upregulated the expression levels of Per2,Cry2,GSK-3β and NR1D1 in the hypothalamus(P<0.05,P<0.01),but downregulated Bmal1 and Clock expression(P<0.05,P<0.01).TWBXD downregulated Bmal1 expression in the hypothalamus(P<0.01)and increased NR1D1 expression(P<0.05).DZP significantly enhanced the expression levels of Per2,Cry2 and NR1D1 in the hypothalamus(P<0.01).JWBXD,TWBXD and DZP improved ASMT expression in the pineal gland(P<0.05).CONCLUSION JWBXD can improve sleep structure and prolong the duration of SWS in rats exposed to simulated high-altitude conditions.The mechanisms may involve the regulation of core clock protein expressions in the hypothalamus,promotion of mela-tonin secretion,and inhibition of HPA axis hyperactivity.