表没食子儿茶素没食子酸酯对束缚应激大鼠行为学表现的影响

EFFECTS OF (-)-EPIGALLOCATECHIN-3-GALLATE ON THE BEHAVIORAL PERFORMANCES OF RATS WITH RESTRAINT STRESS

目的观察绿茶多酚(GTPs)单体成分表没食子儿茶素没食子酸酯(EGCG)对束缚应激大鼠行为学表现的影响。方法 40只健康雄性Wistar大鼠随机分为4组:正常对照(CT)组、束缚应激(ST)组、GTPs干预应激(GST)组和EGCG干预应激(EST)组。以束缚制动的方法建立应激动物模型,GTPs和EGCG以灌胃方式给予,实验周期30d。通过旷场实验及避暗实验检测大鼠的认知行为和学习记忆能力;分别以放免法、双抗夹心ELISA法检测血浆中皮质醇和神经递质含量。结果与CT组相比,ST组在旷场中的潜伏期延长,穿格数明显减少;GST组和EST组与ST组相比有显著性差别。避暗实验显示,与CT组相比,ST组潜伏期显著降低,电击次数出现明显增加,而GST组与EST组潜伏期比ST组显著增长,电击次数显著降低。此外,ST组血浆皮质醇水平明显增加,多巴胺和5-羟色胺水平降低;而GST组与EST组与ST组相比,皮质醇水平降低,多巴胺及5-羟色胺含量升高;EST组比GST组总的行为表现稍好。而且动物的行为表现与血浆皮质醇和神经递质含量之间存在相关关系。结论束缚应激引起动物行为学表现异常,应激激素分泌增加。而适量补充EGCG可改善应激大鼠的行为学表现,提高应激机体的自主活动和探究行为以及学习记忆能力。[营养学报,2013,35(2):167-171]

Objective To explore the effects of （-）-epigallocatechin-3-gallate （EGCG） on the behavioral performances of rats with restraint stress. Methods Forty healthy male Wistar rats were randomly assigned to four groups as follows： normal control （CT） group, stress control （ST） group, stress group with green tea polyphenols （GTPs） modulation （GST） and stress group with epigallocatechin-3-gallate modulation （EST）. The stress model was established by restraint. GTPs and EGCG were given by intragastric administration at dose of 500 mg/（kg · bw）. The changes of behaviors were examined by open-field test and step-through test. The contents of cortisol and neurotransmitters in plasma were detected by radioimmunoassay（RIA） and enzyme linked immunosorbentassay （ELISA） respectively. Results Compared with CT group, the latency of ST group in open-field test was prolonged and the crossing frequency was reduced apparently, while GST group and EST group were different significantly in comparision with ST group; The results of step-through test showed that the latency of ST group was decreased and the shock frequency was increased in comparision with CT group, however, GST group and EST group had opposite results. The content of plasma cortisol in ST group was increased obviously, and the plasma cortisol level in GST and EST groups was lower than that in ST group. In addition, plasma serotonin and dopamine levels of ST group decreased significantly in contrast to CT group, and their levels in GST and EST rats were notably increased in contrast to ST group. Conclusion Restraint stress could impair rat＇s behaviors, and moderate EGCG treatment might improve the behavioral activities of stressed rats.