天麻素对氯苯丙氨酸(PCPA)致失眠小鼠的镇静催眠作用研究

Sedative and Hypnotic Effects of Gastrodin on PCPA-Induced Insomnia Mice

目的:探讨天麻素对对氯苯丙氨酸(PCPA)致失眠小鼠睡眠的改善作用。方法:将KM小鼠随机分为正常对照组、模型对照组、天麻素10、20、40 mg/kg组、地西泮2.6 mg/kg组,除正常对照组外,其余各组采用腹腔连续注射2 d PCPA,建立失眠小鼠模型。造模成功后,各组灌胃给予相应药物,模型对照组及正常对照组灌胃给予相应体积生理盐水,连续6 d,每天称量小鼠体质量并记录其行为变化;第6 d末次给药后,观察腹腔注射戊巴比妥钠诱导小鼠的睡眠发生率、睡眠潜伏期及睡眠时间;苏木精-伊红染色法(HE)观察各组小鼠海马组织病理变化,酶联免疫吸附法(ELISA)检测各组小鼠大脑皮层5-羟色胺(5-HT)含量,蛋白免疫印迹法检测细胞外调节蛋白激酶(ERK)、磷酸化细胞外调节蛋白激酶(p-ERK)、B淋巴细胞瘤-2基因(BCL-2)、白细胞介素-1β(IL-1β)及白细胞介素-6(IL-6)蛋白表达的变化。结果:与正常对照组比较,模型对照组小鼠体质量下降,睡眠发生率下降,睡眠潜伏期延长,睡眠时间缩短(P<0.01),小鼠海马区部分神经元细胞胞核固缩深染,胞质溶解,大量锥体细胞排列紊乱,细胞体积明显变小,胞核固缩,小鼠大脑皮层中5-HT含量减少(P<0.01),IL-6蛋白表达、p-ERK/ERK比值明显升高(P<0.01),BCL-2、IL-1β蛋白表达显著下调(P<0.01);与模型对照组比较,天麻素10、20、40 mg/kg组小鼠体质量恢复,睡眠率升高,睡眠潜伏期缩短,睡眠时间延长(P<0.01),天麻素在一定程度上改善了大脑组织的病变程度,明显恢复脑组织中5-HT含量,明显逆转了IL-6、BCL-2、IL-1β蛋白表达以及p-ERK/ERK比值(P<0.05或P<0.01)。结论:天麻素对PCPA致失眠小鼠的睡眠具有显著的改善作用,其机制可能与调节脑内IL-6、IL-1β、BCL-2蛋白表达以及p-ERK/ERK比值有关。

Objective:To investigate the effects of gastrodin on p-chlorophenylalanine(PCPA)-induced insomnia mice.Methods KM mice were randomized into normal control group,model group,10,20,and 40 mg/kg gastrodin groups,and 2.6 mg/kg diazepam group.Then,the mice,except for the normal control group,received(i.p.)PCPA for 2 consecutive days to induce insomnia.After modeling,mice in gastrodin groups were given(i.g.)corresponding drugs and mice in model group and normal control group the corresponding volume of normal saline for 6 days.The body weight and behavior changes were observed and recorded every day.After the last administration on the 6 th day,the sleep rate,sleep latency,and sleep duration of mice induced by pentobarbital sodium(i.p.)were observed.The pathological changes of hippocampus were detected by hematoxylin-eosin(HE)staining,the content of 5-hydroxytryptamine(5-HT)in cerebral cortex by enzyme linked immunosorbent assay(ELISA),and the expression of extracellular regulated protein kinase(ERK),phosphorylated extracellular signal-regulated protein kinase(p-ERK),B lymphoma-2 gene(Bcl-2),interleukin-1β(IL-1β),and interleukin-6(IL-6)by Western blotting.Results:Compared with the normal control group,the model group demonstrated reduced body weight and sleep rate,long sleep latency,short sleep duration(P<0.01),pyknosis of hyperchromatic nuclei in some neurons,cytoplasmic dissolution,a large number of disordered pyramidal cells,with decreased volume and karyopycnosis,reduced content of 5-HT in cerebral cortex(P<0.01),raised IL-6 expression and p-ERK/ERK ratio(P<0.01),and down-regulated expression of Bcl-2 and IL-1β(P<0.01).Compared with the model group,all gastrodin groups(10,20,and 40 mg/kg)showed body weight recovery,increased sleep rate,short sleep latency,and long sleep duration(P<0.01).Gastrodin alleviated the lesion of brain tissue,significantly restored the content of 5-HT in brain tissue,and significantly reversed the expression of IL-6,Bcl-2,and IL-1β,and the p-ERK/ERK ratio(P<0.05 or P<0.01).Conclusion:Gastrodin can significantly improve the sleep of PCPA-induced insomnia mice,possibly by regulating the expression of IL-6,Bcl-2,and IL-1βin brain tissue and p-ERK/ERK ratio.