目的:以小鼠自主活动次数、脑内乙酰胆碱(acetylcholine,Ach)、谷氨酸(glutamate,Glu)、5-羟色胺(5-hydroxytryptamine,5-HT)及γ-氨基丁酸(gamma amino butyric acid,GABA)含量为指标,探讨北冬虫夏草多糖(Cordyceps militaris polysaccharide,CMP)和总黄酮(Cordyceps militaris flavonoids,CMF)的镇静、催眠作用及机制。方法:将84只ICR(institute of cancer research)小鼠随机平分为空白对照组,CMP 50 mg/kg、100 mg/kg和200 mg/kg剂量组,CMF 50 mg/kg、100 mg/kg和200 mg/kg剂量组7个实验组。分组灌胃给药14 d后,于自主活动仪上观察并记录小鼠自主活动次数;给药30 d后采用酶联免疫吸附分析法(enzymelinked immuno sorbent assay,ELISA)测定小鼠脑组织中5-HT、Ach、Glu和GABA含量。采用噻唑蓝(methylthiazolyldiphenyl-tetrazolium bromide,MTT)比色法测定CMP和CMF对大鼠肾上腺嗜铬细胞瘤(rat adrenal pheochromocytoma cell line,PC12)细胞增殖的影响。结果:自主活动实验结果显示CMP及CMF 100 mg/kg和200 mg/kg剂量组小鼠的活动次数均较空白对照组明显减少(P=0.000);神经递质水平测定结果表明,与空白对照组比较,CMP 100 mg/kg、200 mg/kg剂量组和CMF 50 mg/kg剂量组均能显著降低小鼠脑内Glu水平(P=0.000),CMP和CMF 200 mg/kg剂量组均能明显降低小鼠脑内Ach水平(P值分别为0.003和0.000)、升高5-HT水平(P=0.000),但对GABA水平无明显影响。MTT实验结果表明,CMP和CMF对PC12细胞均无毒性,而且CMP的1μg和0.1μg组还能显著促进正常PC12细胞增殖(P=0.000)。结论:北冬虫夏草具有一定的镇静催眠作用,升高脑内5-HT水平、降低Ach、Glu水平可能是其发挥镇静催眠作用的主要机制之一。 OBJECTIVE: To observe the number of spontaneous activity in mice, the content of brain acetylcholine (Ach), glutamate (Glu), 5-hydroxytryptamine (5-HT) and gamma amino butyric acid , GABA) as indexes to investigate the sedation, hypnotic effect and mechanism of Cordyceps militaris polysaccharide (CMP) and total flavonoids (CMF). Methods: Totally 84 ICR (institute of cancer research) mice were equally divided into blank control group, CMP 50 mg / kg, 100 mg / kg and 200 mg / kg, CMF 50 mg / kg and 100 mg / kg 200 mg / kg dose group of 7 experimental groups. After 14 days of intragastric administration, the number of spontaneous movement of mice was observed and recorded on the autonomic activity meter. After 30 days of administration, the levels of 5 (superscript +) in mouse brain were measured by enzyme linked immunosorbent assay (ELISA) -HT, Ach, Glu and GABA content. The effects of CMP and CMF on the proliferation of rat adrenal pheochromocytoma cell line (PC12) were determined by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. Results: The results of autonomic activity showed that the number of activities of mice in CMP and CMF 100 mg / kg and 200 mg / kg groups were significantly decreased compared with the control group (P = 0.000); neurotransmitter levels showed that compared with the blank control (P = 0.000). The levels of Glu in brain of mice treated with CMP 100 mg / kg, 200 mg / kg and CMF 50 mg / kg decreased significantly Significantly decreased Ach levels (P values ​​were 0.003 and 0.000, respectively) and increased 5-HT levels (P = 0.000), but had no significant effect on GABA levels. The results of MTT assay showed that both CMP and CMF were non-toxic to PC12 cells, and 1μg and 0.1μg CMP could significantly promote the proliferation of normal PC12 cells (P = 0.000). Conclusion: Cordyceps sinensis has a certain sedative and hypnotic effects. Elevated 5-HT levels and decreased Ach and Glu levels may be one of the main mechanisms of sedation and hypnosis.