%0 Journal Article %T Corticosterone impairs cultured hippocampal neurons and facilitates Ca2+ influx through voltage-dependent Ca2+ channel %A Zhou Jian-Zheng %A Zheng Jian-Quan %A Zhang Yong-Xiang %A Zhou Jin-Huang %J Acta Pharmacologica Sinica %D 2016 %B 2016 %9 %! Corticosterone impairs cultured hippocampal neurons and facilitates Ca2+ influx through voltage-dependent Ca2+ channel %K %X "AIM: To investigate the effect of corticosterone (Cor) on the viability of cultured hippocampal neurons as well as voltage-dependent Ca2+ channel (VDCC) on the membrane of the hippocampal neurons. METHODS: The primary cultured hippocampal neurons were prepared and the viability of hippocampal neurons was determined by MTT assays. Inward Ca2+ currents of VDCC on the membrane of the hippocampal neurons were measured with the whole-cell patch-clamp technique. RESULTS: Treatment with Cor concentration-dependently reduced the survival of hippocampal neurons. The IC50 of Cor was 3.2 mumol.L-1. Neurons from cerebral cortex were affected only by high concentrations of Cor (10 mumol.L-1 and 0.1 mmol.L-1) with the IC50, 85 mumol.L-1, 20 times larger than the former. Whole-cell patch-clamp experiment showed that Cor (1 mumol.L(-1)-0.1 mmol.L-1) sprayed to the surface of the hippocampal neurons instantly facilitated Ca2+ influx through VDCC with the maximal elevation of 53%, 191%, and 84% above the baseline respectively and this effect was shown to be concentration-independent. In addition, changing the membrane potentials from -40 mV to -10 mV did not affect the facilitating effect of Cor on the Ca2+ influx, indicating that Cor-induced Ca2+ influx was membrane potential-independent. CONCLUSION: Cor markedly facilitated Ca2+ influx into the hippocampal neurons, which may be one of the important mechanisms underlying the neurotoxicity of Cor to hippocampus." %U http://www.chinaphar.com/article/view/7311 %V 21 %N 2 %P 156-160 %@ 1745-7254