细胞内钙离子在高温诱导海马神经元凋亡中的作用机制

目的探讨Ca2+在高温诱导海马神经元凋亡中的作用,为丹曲林钠在热致脑损伤疾病中的应用提供实验依据。方法通过体外建立高温诱导原代培养的海马神经元凋亡模型,应用Ca2+特异性阻断剂丹曲林钠,观察其对神经元凋亡率、细胞内Ca2+荧光强度及其动态变化的影响。结果丹曲林钠能够明显降低高温处理后海马神经元的凋亡率;42℃处理并加入丹曲林钠组的扫描结果显示,Ca2+荧光强度为107.35±6.0,较正常培养的细胞内Ca2+荧光强度(159.12±33.8)明显降低,加入丹曲林钠20～25s后Ca2+浓度即开始下降,约50s后下降至最低值,然后稳定于低于原来基线的水平。结论丹曲林钠在高温诱导的海马神经细胞凋亡中具有重要的保护作用,在预防热致脑损伤疾病中具有一定的应用价值。

Mechanism of Ca2+ on the hyperthermia-induced apoptosis of rat hippocampal neurons in vitro

OBJECTIVE: To study the mechanism of Ca(2+) on the apoptosis induced by hyperthermia in neonate rat hippocampal neurons to provide the applicative evidence of dantrolene for preventing brain injuries. METHODS: Dantrolene, Ca(2+) specific blocking agent, was used in the hyperthermia-induced apoptosis of primary hippocampal neurons in vitro to observe its effect on the apoptosis, fluorescent intensity, and dynamic change of Ca(2+) by flowcytometry and laser confocal microscopy. RESULTS: The rate of apoptosis was decreased significantly after hyperthermia treatment by dantrolene sodium. The intracellular Ca(2+) fluorescent intensity in 42 degrees C treatment group (107.35 +/- 6.0) was significantly lower than that in control group (159.12 +/- 33.8). The concentration of Ca(2+) began to decrease 20 approximately 25 s after adding dantrolene sodium, and reached the lowest level about 50 s later, and then kept lower than the basal level. CONCLUSION: Dantrolene sodium has an important protective effect on hippocampal neurons apoptosis induced by hyperthermia and may have some applicative value of preventing heat-induced brain injury.