孕期应激对子代雌鼠成年后钙结合蛋白Parvalbumin和Calretinin表达的影响

Effect of prenatal stress on the expression of Parvalbuminand Calretinin in adult female rat offspring

目的探讨孕期应激对子代雌鼠成年后钙结合蛋白阳性神经元表达的影响。方法 6只SD孕鼠随机分为孕期应激组(PS组)和对照组(CON组)。PS组孕鼠在妊娠晚期接受限制性应激,CON组不给予孕期应激。子代成年后,PS组和CON组雌性子代随机分别又分为PS-S组,PS-NS组,CON-S组和CON-NS组(n均=6)。PS-S组和CON-S组动物先后接受限制性应激和冰水应激。动物在接受应激后均给与水和酒精喂养,用Western blot检测海马钙结合蛋白Parvalbumin(PV)和Calretinin(CR)蛋白的表达,进一步结合共聚焦免疫荧光组织化学方法检测PV和CR在海马CA1、CA3区和齿状回(dentate gyrus,DG)的表达。结果与CON-NS组相比,海马区PV和CR的蛋白表达在CON-S,PS-NS和PS-S组下降,以PS-S组表达最低。PV在海马CA1、CA3区和DG的免疫荧光结果与PV的蛋白表达呈一致性,免疫阳性细胞明显减少;而CR的表达除了在海马CA1区的PS-NS组略有升高外,在其余各组的表达均较减少。与CON-NS组相比,PV和CR在其它各组的蛋白表达和免疫阳性细胞计数差异有统计学意义,其中以PS-S组的表达降低最为有统计学意义(P<0.05)。结论孕期应激可影响子代雌鼠成年后海马结构钙结合蛋白PV和CR的表达。

Objective To observe the effect of prenatal stress on the expression of Parvalbumin（PV） and Calretinin（CR）in adult female rat offspring. Methods Six pregnant SD rats were randomly divided into a prenatal stress （PS） group and a control group （CON）. Rats in PS group were subjected to restraint stress during the late gestational periods, while rats in the control group were not given prenatal stress. The adult female offspring were randomly divided into PS plus stress group （PS-S） and PS without stress group （PS-NS）, CON plus stress group （CON-S） and CON plus no stress group （CON-NS）. The rats in PS-S and CON-S were subjected to restraint and ice-water stress. All rats were offered free choice between water and ethanol solution. After model establishment, brain tissues were harvested, the levels of PVand CR proteins in the hippocampus were detected by Western blot. Furthermore, PV and CR expression in hippocampus CA1, CA3 and dentate gyrus were determined with confocal immunofluorescence. Results Compared to CON-NS group, the protein of PV and CR in the hippocampus was meaningfully decreased in CON-S, PS-NS and PS-S groups, with the lowest being in the PS-S group. The immunofluorescent results of PV and CR in hippocampus CA1, CA3 and dentate gyrus were in agreements with the PV protein expression, which showed obviously decreased positive staining cells. Statistic analysis showed PV and CR expression had a significant difference between CON-NS and other groups, with most significant decrease of expression being in the PS-S group （P〈0.05）. Coclusion Prenatal stress may directly affect the calcium binding proteins PV and CR in the hippocampus of adult female rat offspring.