摘要
目的初步探讨母子隔离应激对幼鼠海马CA1区锥体神经元自发性放电特征和海马GABAA受体α1亚单位表达的影响及其与癫痫易感性的关系。方法 54只新生的SD大鼠幼鼠用于实验,雌雄不拘,随机分成3组(n=18),正常组(正常喂养,每天不用隔离)、隔离15min组、隔离3h组。在生后16d,3组幼鼠分别行氯化锂-匹罗卡品诱导的惊厥实验,全细胞膜片钳检测海马CA1区锥体神经元自发性放电特征,灌注取脑免疫组化检测海马GABAA受体α1亚单位表达情况。结果隔离3h组体质量(24.60±1.89)g与正常组体质量(29.44±2.03)g比较明显减轻(P<0.05)、幼鼠诱发惊厥的潜伏期隔离3h组(11.50±2.10)min短于正常组(15.32±1.34)min(P<0.05)、海马CA1区锥体神经元自发性放电频率隔离3h组(3.64±2.84)Hz要明显快于正常组(1.15±0.69)Hz(P<0.01)、海马CA1区GABAA受体α1亚单位累计化学光密度,隔离3h组(161.10±5.70)少于正常组(175.40±7.20)(P<0.01)。隔离15min组幼鼠体质量(29.34±1.85)g、诱发惊厥的潜伏期(16.47±1.73)min、海马CA1锥体神经元自发性放电频率(1.36±0.83)Hz、海马CA1区GABAA受体α1亚单位累计化学光密度(171.50±6.80),在以上几方面隔离15min组和正常组比较均无统计学差异(P>0.05)。结论早期母子隔离3h的应激对幼鼠生长发育、癫痫易感性产生不良影响,海马CA1锥体神经元兴奋性增加、GABAA受体α1亚单位表达减少可能作为其潜在的病理机制之一。
Objective To study the effect of stress due to mother and infant isolation on spontaneous discharge of pyramidal neurons in hippocampal CA1 and expression of hippocampal GABAA receptor α1 in infantile rats,and its correlation with susceptibility to epilepsy.Methods Infantile rats were randomly divided into normal group,15-min isolation group,and 3-h isolation group.Sixteen days after birth,convulsion was induced in rats with lithium chloride-pilocapine.Characteristics of spontaneous discharge of pyramidal neurons in hippocampal CA1 were detected with whole-cell patch clamps.Expression of hippocampal GABAA receptor α1 in perfused brain tissue was detected with immunohistochemistry.Results The body weight was significantly lower,the susceptibility to convulsion and the excitability of pyramidal neurons in hippocampal CA1 were higher,and the expression level of hippocampal GABAA receptor α1 in brain tissue was lower in 3-h isolation group than in normal group.However,no significant difference was found in the above parameters between 15-min isolation group and normal group.Conclusion Stress due to 3-h mother and infant isolation may produce adverse effects on the growth and development,and susceptibility to epilepsy of infantile rats.Increased excitability of pyramidal neurons in hippocampal CA1 and decreased expression of hippocampal GABAA receptor α1 in brain tissue may be one of the potential mechanisms.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2010年第13期1442-1445,共4页
Journal of Third Military Medical University
