Better calcium homeostasis was maintained in cortical neurons of ground squirrels than rats in prolo

• 作 者: JuanjuanZhao;ShanGao;JunzhanJing;ZhenChai;
• 机 构: State Key Laboratory of Biomembrane and Membrane Biotechnology,College of Life Sciences,Peking Unive
• 出 处: International Conference for Physiological Sciences 2012(201
• 发表日期: 2012年期

　　Excitotoxicity is one of the leading causes inducing neuronal death.Here, we reported that cultured cortical neurons from a mammalian hibernating species-Citelus dauricus (GS) better survived glutamate toxicity compared with rat neurons.GS neurons maintained much lower intracellular calcium concentration ([Ca2+]i) 3 h,even 24 h after glutamate application.Channels and transporters contributing to [Ca2+]i elevation and removal were then studied.Not surprisingly, the stimulated amplitude of [Ca2+]i elevation as well as the decay time constant in GS neurons was both significantly smaller.The roles of three main Ca2+ exclusion apparatuses (SERCA, NCX and mitochondria) were further considered.It turned out that none of them fully explained the faster velocity in GS neurons, suggesting the existence of other calcium exclusion mechanisms.Taken together, our studies suggested GS cortical neurons were more tolerant to excitotoxicity, during which they maintained better calcium homeostasis by a smaller [Ca2+]i elevation and a faster calcium removal rate.