热应激对小鼠神经元骨架蛋白和热休克蛋白70表达的影响

Effects of heat stress on the expression of skeleton protein and heat-shock protein in mice cortex neuron

目的观察不同温度下体外培养的小鼠皮层神经元的形态及骨架蛋白表达变化，以及与热休克蛋白70（HSP70）变化的关系。方法取小鼠胚胎大脑皮层进行神经元原代培养，7天后给予不同温度刺激，应用倒置相差显微镜观察刺激后神经元的形态变化，应用激光共聚焦扫描观察不同温度刺激后神经元中骨架蛋白（β-tubulin）、HSP70的表达变化。结果光镜观察见38℃时漂浮细胞增加，神经网络稀疏；39℃时部分细胞坏死；42℃时大部分细胞出现坏死，胞体碎裂，突起漂浮或消失。激光共聚焦扫描见高温（38-42℃）刺激后β-tubulin荧光强度低于37℃时，且温度愈高荧光强度降低愈明显；HSP70荧光强度呈钟形分布，39℃最高，37℃、42℃较低。结论热应激可以导致神经元形态变化，β-tubulin结构紊乱可能是其原因之一，HSP70也可能参与了该病理过程。

Objective To observe the morphological changes of mice cortex neuron cultured in vitro under different temperature, and the expression of skeleton protein （β-tubulin） in the neuron, and to study the relationship between β-tubulin and heat shock protein 70 （HSP70）. Methods The cerebral cortex neuron of embryonic mice was cultured in vitro. The cultured neuron was put in different temperature 7 days later. To observe the morphological changes of the neuron using optical microscope and the changes of the expression of tubulin and HSP70 under different temperature using laser scanning confocal images. Results Optical microscopy indicated that drifting cells increased, and neural network became sparse in 38℃ ; some cells necrosed in 39℃ ; most cells necrosed, cell broke to pieces, axons drifted or disappesared in 42℃. Results of laser scanning confocal images indicated that after hyperthermia the fluorescence intensity of β-tubulin was lower than that of controls, and the fluorescence intensity declined as the temperature elevated. The fluorescence intensity of HSP70 showed a bell-shape distribution curve, i. e. the highest value emerged at 39℃, whereas the lower values appeared at 37℃ and 42℃. Conclusion Heat stress leaded to the morphological changes of neuroru The disordered of skeleton protein may be responsible for the changes and HSP70 may take part in the process.