高湿热刺激对大鼠下丘脑内神经元和星形胶质细胞可塑性变化的影响

目的 探讨高湿热环境下大鼠下丘脑的室旁核和视上核内神经元和星形胶质细胞的可塑性变化及其相互关系.方法 将大鼠置于仿真模拟气候舱[干球温度(40.0±0.5)℃,相对湿度(60±5%)]内,120 min后取出.采用免疫组织化学方法,观察Fos和GFAP在下丘脑室旁核和视上核中的表达并计录各组动物的行为学反应.结果 在高湿热环境下行为学上动物表现为躁动不安、呼吸加快、前爪抓挠面部;120min组中有2只动物死亡.免疫组织化学观察发现湿热刺激组下丘脑室旁核和视上核中的Fos和GFAP表达比对照组明显上调,两组之间差异有统计学意义.结论 机体下丘脑的室旁核和视上核中的神经元和星形胶质细胞共同参与了对高湿热刺激的反应及其调节过程.

Changes in plasticity of rat hypothalamic neurons and astrocytes in humid and hot environment

OBJECTIVE: To study the changes in the plasticity of the neurons and astrocytes in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the hypothalamus of rats exposed to a humid and hot environment. METHODS: The rats were subjected to stimulation with a humid and hot environment for 120 min in a climate chamber (dry bulb temperature of 40.0-/+0.5 degrees C with relative humidity of 60-/+5%). During the exposure, the behavioral responses of the rats were observed, and the changes in the expressions of Fos and GFAP in the PVN and SON in response to the exposure evaluated using immunohistochemical ABC methods. RESULTS: Exposure to a humid and hot environment caused restlessness and agitation in the rats, which showed increased respiratory frequency and scratching of the face with the forelimbs. Two rats died after the 120-min exposure. Significantly increased expressions of Fos and GFAP were detected in the PVN and SON following the exposure as compared with the control group. CONCLUSION: The neurons and astrocytes in the PVN and SON both participate in the regulation of responses to exposure to a humid and hot environment.