热应激对大鼠中枢神经肽Y及阿黑皮素基因表达的影响

摘要

ObjectiveTo investigate the effects of heat stress at different time points on the levels of stress hormones in the central HPA axis and peripheral blood of rats.Methods36 male SD rats were randomly divided into three groups:control group (24℃), high temperature short time group (38℃, 1h) and high temperature moderate time group (38℃, 6h).After two weeks of heat exposure, the spleen, thymus, hypophysis and hypothalamus were removed to calculate relative organ weight.Enzyme linked immunosorbent assay (Elisa) was used to measure the levels of Cor, EPI, and HSP70 in plasma.Real-time fluorescence quantification was used to detect the expression of NPY and POMC m RNA.ResultsThe relative quality of pituitary gland was lower in the high-temperature medium-time group than in the control group, while it was higher in hypothalamus than that in the control group (P＜0.05).The levels of Cor and EPI in the two high-temperature groups were higher than those in the control group.The content of HSP70 in the high-temperature medium-time group was higher than those in the control group and the high-temperature short-time group (P＜0.05).The NPY m RNA expression of two kinds of high temperature groups was higher than the control group.The POMC m RNA expression of high temperature moderate time group was significant higher than the control group (P＜0.05).Conclusion Heat stress can significantly increase the gene expression levels of central NPY and POMC, which are related to the adaptive response of the body to changes in the external environment.%目的 探讨不同时间的热应激对大鼠中枢HPA轴及外周血中热应激相关因子水平的影响.方法 36只雄性SD大鼠随机分为3组:对照组(24℃)、高温短时间组(38℃,1h)、高温中等时间组(38℃,6h).经2周热暴露后,取大鼠脾脏、胸腺、垂体、下丘脑计算器官相对质量;酶联免疫吸附法测定血浆中皮质醇(Cor)、肾上腺素(EPI)及热休克蛋白70(HSP70)含量;实时荧光定量PCR测定下丘脑神经肽Y(NPY)及垂体阿黑皮素(POMC)的基因表达.结果 高温中等时间组的垂体相对质量低于对照组,而下丘脑高于对照组(P均＜0.05);两种高温组的Cor及EPI含量均高于对照组,高温中等时间组的HSP70含量高于对照组及高温短时间组(P均＜0.05);两种高温组的NPY基因表达水平均高于对照组(P均＜0.05),高温中等时间组的POMC基因表达水平高于对照组(P＜0.05).结论 热应激可提高大鼠中枢神经肽Y及阿黑皮素的基因表达水平,与机体对外界环境变化的适应性反应有关.