热惊厥幼龄大鼠脑内Prolactin蛋白及Zinc transporter 1 mRNA表达

目的 探讨热应激(Heat stress,HS)和热惊厥(Febrile convulsions,FC)对脑内催乳素蛋白(Prolactin,PRL)和锌离子转运体1(Zinc transporter 1,ZnT1)表达的影响,探讨FC的神经免疫学机制.方法 实验在浙江大学附属邵逸夫医院中心实验室进行.采用热水浴诱导FC模型.21 d龄雄性sD大鼠随机分为正常对照组(8只)和热应激组(28只),28只热应激处理大鼠中15只达到5级(设为热性惊厥组,FC),10只未出现惊厥(设为单纯热应激组,HS),3只达到2级惊厥,弃用.应用免疫组织化学技术对HS和FC大鼠PRL免疫反应性在不同脑区的表达进行分析,原位杂交检测ZnT1表达.各组阳性细胞数采用方差分析进行统计.结果 ①对照组大脑皮层偶见零星表达,着色淡且无定位分布特征.HS组PRL-IR阳性细胞在大脑皮层PIR、Ent和Rs区免疫染色较深,PRH、PAR和Fr区染色较浅;另外PRL-IR阳性细胞还分布于丘脑中线一带;而FC组则于大脑皮层、海马、杏仁核、丘脑及下丘脑见大量PRL-IR阳性细胞,呈弥漫性分布,无明显核团分布特征.②HS和FC两组大脑皮层各区PRL-IR阳性细胞数均明显高于对照组(P<0.01).FC组大鼠大脑皮层PIR、Ent、RS区PRL-1R阳性细胞数与HS组大鼠差异无统计学意义(F值分别为688.9、744.3、0.56,P>0.05),PRH和PAR区FC组明显高于HS组(F值分别为2.68、1.48,P<0.01).③FC组海马区域可见明显ZnT1 mRNA表达,而HS组和对照组无明显表达.结论 ①PfuL在HS组和FC组大脑皮层各区明显表达,而FC组在海马和杏仁核等前脑结构内亦有明显表达,表明PRL不仅与热应激的中枢调控有关,也参与海马等前脑结构对惊厥活动的中枢调控机制.②FC组海马ZnT1 mRNA明显表达提示FC组海马区域存在异常增高的锌离子转运.

Prolactin protein and Zinc transporter 1 mRNA expressions in weanling rats following heat stress and febrile convulsions

Objective To analyze the expression of prolactin protein and ZnT1 mRNA in rat brain in the wake of heat stress and febrile convulsion(FC).Method Thirty-six weanling Spragne-Dawley rats were randomly divided into control group(n=8) and other 28 rats were used to induce heat stroke by warm water but three of them failed to produc expected heat stress.Consequently,there were 35 rats eligible to be models of heat stroke,and of them,10 rats showed heat stress(HS group,n=10) and 15 rats had 5-grade febrile convulsion (FC group,n = 15).The inmmunohistocbemistry and in situ hybridization method were used in this study.The IR) neurons were found in the rats of control group.The deep immune staining was found in the PIR,Era and RS regions of cerebral cortex and light immune staining was found in the PRH,PAR and FR regions of cerebral cortex in HS group.In addition,the PRL-IR positive neurons were found around the midline strip of thalamus without characteristic subnucleus-specific distribution.However,abundant induction of PRL-IR positive neurons with diffuse distribution were found in cerebral cortex,hippoeampus,amygdala,thalamus and hypotha]amns of rats in FC and FC rats showed more PRD-IR positive neurons in cerebral cortex than those in rats of control group (P