甘丙肽及其受体在孕期应激大鼠新生子代前额叶皮层和海马脑区表达的性别差异

Gender difference of galanin and its receptors expression in prefrontal cortex and hippocampus in prenatal stress rat offspring

目的探讨SD大鼠孕期应激对子代前额叶皮层(PFC)和海马脑区发育的影响。方法 SD雌鼠12只,随机分为对照组和孕期应激组,建立大鼠孕期应激模型(孕8~21d期间,束缚应激2h/d),子代出生当天,称量体重,计算雌雄比例;各组按窝别随机取雌雄子鼠各6只,取PFC和海马,采用实时定量PCR(Q-PCR)方法检测两组的雌雄性子代PFC和海马脑区甘丙肽(GAL)、甘丙肽受体(GALRs)、脑源性神经营养因子(BDNF)和酪氨酸激酶B(TrkB)的表达,分析两组子代各指标的差异。结果与对照组比较,孕期应激组子代大鼠体重明显降低[(6.45±0.19)vs.(7.57±0.23)g],差异具有统计学意义(P<0.01);孕期应激组雌性子代有增加趋势,但差异无统计学意义(P>0.05)。孕期应激组雄性子代PFC脑区的TrkB mRNA表达较对照组显著增加[(1.35±0.12)vs.(1.00±0.07)],雌性子代PFC脑区GALR1mRNA及BDNF mRNA表达水平较对照组显著降低[分别为(0.51±0.13)vs.(1.04±0.11)、(0.73±0.07)vs.(1.11±0.10)](P均<0.05)。雌性子代海马脑区的GAL mRNA表达较对照组显著增高[(2.51±0.18)vs.(1.00±0.11)],BDNF mRNA表达显著降低[(0.75±0.05)vs.(1.00±0.03)](P均<0.05)。结论大鼠孕期应激可对子代大鼠脑发育产生影响,雌性子代较雄性子代更敏感。

Objective：To investigate the effects of prenatal stress on the development of the prefrontal cortex（PFC）and hippocampus of the offspring of SD rats.Methods： Twelve SD female rats were randomly split into control and pregnancy stress group.In pregnancy stress group,the stress model of the rats was established（2 hours per day of restraint stress during 8-21 days of pregnancy）.The weight of descendant on the day of birth and the number of male and female ratio were recorded.Six male and six female offspring for each group were killed to collect PFC and hippocampus.The expression of galanin（GAL）,galanin receptor（GALRs）,brain-derived neurotrophic factor（BDNF）and tyrosine kinase B（TrkB）in PFC and hippocampus were detected using Q-PCR method,and the differences between the two groups of offspring were analyzed.Results：Compared to control group,the birth weight of the offspring in the prenatal stress group was significantly decreased[（6.45±0.19）vs.（7.57±0.23）g]（P〈0.05）.The ratio of female offspring in prenatal stress group had an increasing trend,but the difference was not significant（P〈0.05）.In male descendants,the expression of TrkB in the PFC was significantly increased compared with the control group[（1.35±0.12）vs.（1.00±0.07）]（P〉0.05）.In the female descendants,the expressions of GALR1 mRNA[（0.51±0.13）vs.（1.04±0.11）]and BDNF mRNA[（0.73±0.07）vs.（1.11±0.10）]in the PFC were significantly decreased compared with the control group（P〈0.05）.The expression of GAL mRNA in hippocampus was significantly increased[（2.51±0.18）vs.（1.00±0.11）]（P〈0.05）,and the expression of BDNF mRNA was significantly decreased[（0.75±0.05）vs.（1.00±0.03）]compared with the control group（P〈0.05）.Conclusions：Prenatal stress can affect the brain development of offspring rats.Female offspring were more susceptible to pregnancy stress than male.