皮质酮快速升高大鼠脊髓背角神经元钙浓度

Rapid elevation of calcium concentration in rat dorsal spinal neurons by corticosterone

目的:观察皮质酮(CORT)对培养的脊髓背角神经元Ca2+浓度([Ca2+]i)的调节作用及机制。方法:培养新生SD大鼠脊髓背角神经元,激光共聚焦显微镜检测神经元[Ca2+]i的变化。结果:CORT可快速升高培养的脊髓背角神经元[Ca2+]i,且呈现剂量依赖性(P<0.05);CORT诱导的神经元[Ca2+]i升高是以外钙内流为主(P<0.01);百日咳毒素(G蛋白活化阻断剂)可阻断CORT所致的脊髓背角神经元[Ca2+]i升高(P<0.01),而糖皮质激素受体拮抗剂RU38486对CORT的效应无抑制作用。结论:CORT通过非基因组途径快速增高培养的脊髓背角神经元[Ca2+]i。

Objective： To explore the modulatory effects of corticosterone （CORT） on the intracellular calcium concen- tration （ [Ca2＋ ]i） in cultured rat dorsal spinal neurons and the relative mechanism. Methods：Neurons from neonatal SD rat spinal cord were cultured. Confocal laser scanning microscopy were employed to detect changes of [ Ca2＋ ] i in cultured neurons. Results：CORT （0.1-10 μmo]/L） caused a rapid increase in [ Ca2＋ ]i with a dose-dependent manner in cul- tured dorsal spinal neurons. The action of CORT on neuronal [ Ca2＋] i was blocked by pertussis toxin （ a blocker of G protein activation, 100 ng/ml） , but was unaffected by RU38486 （glueocorticoid receptor antagonist, 10 μmol/L）. Con- clusion ： These observations suggest that CORT can rapidly increase [ Ca2＋ ] i in cultured rat dorsal spinal neurons through a nongenomic mechanism.