不同温度热应激时大鼠下丘脑内胶质原纤维酸性蛋白的表达变化

EXPRESSION OF GFAP IN RAT HYPOTHALAMUS AFTER DIFFERENT TEMPERATURE HEAT STRESSES

目的探讨不同温度下,大鼠下丘脑内胶质原纤维酸性蛋白(GFAP)的表达情况。方法将成年SD大鼠40只置于24℃、34℃、38.5℃、42℃(10只/每组温度),相对湿度为60%的实验仓内,60min后取出,常规方法灌流固定取脑,下丘脑恒冷箱制片(30μm),应用抗GFAP免疫组织化学标记法和抗GFAP与Fos双重免疫组织化学标记方法,观察大鼠急性热应激后,星形胶质细胞在下丘脑内的形态、分布和数量的变化。结果24℃时,下丘脑内GFAP阳性细胞较少;34℃时,GFAP在下丘脑内各个核团(下丘脑前区、室旁核、弓状核、视交叉上核和视上核)表达增加,38.5℃时,GFAP表达明显增加,达到峰值;42℃时又降低,并且出现了Fos阳性的星形胶质细胞。结论星形胶质细胞参与了热应激的病理生理过程。

Objective To investigate the expression of GFAP in rat hypothalamus after acute heat stress. Methods The rats were caged in a experimental incubator for 60 minutes, the temperature within the incubator was adjusted to 24℃ ,34℃, 38.5℃ or 42℃, the humidity was 60%. Single anti-GFAP i （ABC） method and anti-Fos and GFAP double immunohistochemical method were used to observe the expression of GFAP in hypothalamus in different ambient temperatures after heat stress. Results The GFAP-positive cells were rare in hypothalamus at 24℃, however it was increased in many nuclei （anterior hypothalamic area, paraventricular nucleus, arcuate nucleus, suprachiasmatic nucleus and supraoptic nucleus）at 34℃ and peaked when ambient temperature was 38.5℃, and then decreased. However, Fos/GFAP-IR double labelled astrocytes were observed at 42℃. Conclusion Astrocytes participate in the pathophysiological process of heat stress.