Objective To observe the effects of acupuncture at acupoints along the meridians on the expression of frontal lobe associated protein kinase in pchlorophenylalanine(PCPA)induced insomnia rats;To explore the mechanism of acupuncture in improving insomnia.Methods Totally 60 rats were randomly divided into blank group,model group,sham acupuncture group,acupuncture group and Western medicine group,with 12 rats in each group.An insomnia model rat was induced by intraperitoneal injection of PCPA.The acupuncture group received acupuncture at"Baihui","Shenmen"(bilateral),and"Sanyinjiao"(bilateral),while the sham acupuncture group only fixed the needle at the corresponding acupoints but did not penetrate the skin,while the model group was only fixed for 30 minutes,the Western medicine group was given a solution of estazolam by gavage for 7 consecutive days,the blank group was not treated.The pentobarbital sodium reversal experiment was used to detect the sleep latency and sleep time of rats,ELISA was used to detect the content of melatonin(MT)in plasma,RT-PCR was used to detect the mRNA expressions of calmodulin dependent protein kinase(CaMK)Ⅱ,protein kinase C(PKC)and p38 mitogen activated protein kinase(MAPK)in frontal lobe tissue,and Western blot was used to detect the protein expressions of CaMKⅡ,PKC and p38MAPK in frontal lobe tissue.Results Compared with the blank group,the sleep latency of the model group rats were significantly prolonged and the sleep time were significantly shortened(P<0.01),the content of MT in plasma was significantly reduced(P<0.01),and the mRNA and protein expressions of CaMKⅡ and PKC in frontal lobe tissue were significantly decreased(P<0.01),the mRNA and protein expressions of p38MAPK were significantly increased(P<0.01).Compared with the model group,the sleep latency were significantly shortened and the sleep time were significantly prolonged in the acupuncture group and the Western medicine group(P<0.01),the plasma MT content significantly increased(P<0.01),the mRNA and protein expressions of CaMKⅡ and PKC in frontal lobe tissue significantly increased(P<0.05),and the mRNA and protein expression of p38MAPK significantly decreased(P<0.01).Compared with the sham acupuncture group,the sleep latency shortened and sleep time were significantly prolonged in the acupuncture group and the Western medicine group(P<0.01),plasma MT content significantly increased(P<0.01),PKC mRNA expression in frontal lobe tissue significantly increased(P<0.01),and p38MAPK mRNA expression significantly decreased(P<0.01).There was no statistically difference in various indicators between the acupuncture group and the Western medicine group(P>0.05).Conclusion Acupuncture at acupoints along the meridians can shorten the sleep latency and prolong sleep time,improve sleep status by regulating the expression of associated protein kinase in frontal lobe of insomnia rats.