产前应激对子代大鼠海马CA3区神经元高电压激活Ca2+通道动力学特征的影响

目的探讨产前应激对子代大鼠海马CA3神经元高电压激活(HVA)钙通道动力学特征的影响。方法给予孕鼠束缚应激,急性分离子代海马CA3神经元,应用全细胞膜片钳技术,研究产前应激对子代大鼠海马CA3区神经元高电压激活Ca2 通道的影响。结果产前应激增加了子代海马CA3神经元高电压激活钙电流幅值、电流面积,而未改变其电导-电压关系、稳态失活动力学、时间到峰等指标。对照组和产前应激组子代海马CA3神经元高电压激活最大钙电流幅值分别为(-40.89±0.31)pA/pF和(-49.44±0.37)pA/pF(P<0.01)。最大电流面积分别为(106.81±4.20)nA*ms和(133.49±2.59)nA*ms(P<0.01)。结论在胎儿发育的关键时期,给予母体应激,对子代海马神经元离子通道产生持续的影响。

Effects of prenatal stress on kinetic properties of high-voltage-activated Ca2+ channel in freshly isolated offspring rat hippocampal CA3 pyramidal neurons

OBJECTIVE: To investigate the effects of prenatal stress (PNS) on kinetic properties of high-voltage-activated (HVA) Ca(2+) channel in freshly isolated offspring rat hippocampal CA3 pyramidal neurons. METHODS: The pregnant rats were exposed to restraint stress, and the hippocampal CA3 pyramidal neurons were freshly isolated from the offspring rats to record voltage-gate Ca(2+) channel currents in these neurons using whole-cell configuration of patch-clamp technique. RESULTS: PNS significantly increased HVA calcium current density and integral current but did not alter the steady-state activation and steady-state inactivation properties of HVA Ca(2+) channel in the offspring rat CA3 neurons. The maximal HVA calcium current density was -40.89-/+0.31 pA/pF in the control group (n=10) and -49.44-/+0.37 pA/pF in PNS group (n=8, P<0.01). The maximal integral current of the HVA Ca(2+) channel was 106.81-/+4.20 nA*ms in the control group (n=10) and 133.49-/+2.59 nA*ms in the PNS group (n=8, P<0.01). CONCLUSION: Maternal exposure to stress during the critical phase of pregnancy may result in long-lasting effects on the ion channels of the hippocampal neurons in the offspring rats.