渗透压变化对缝隙连接蛋白在培养的大鼠下丘脑星形胶质细胞和神经元表达的影响

目的观察渗透压改变对培养的下丘脑星形胶质细胞的缝隙连接蛋白Connexin43（Cx43）和神经元的缝隙连接蛋白Cx32表达的影响。方法体外培养孕14d或新生1d SD大鼠下丘脑的神经元和星形胶质细胞并进行纯化和鉴定。实验各分两组，第1组：细胞由等渗培养液移至高渗培养液（含9％NaCl）分别放置1min、3min、5min、10min和15min后将液体吸出常规固定；第2组：细胞先置于高渗培养液中15min后换成等渗培养液，分别在1min、3min、5min和10min后将等渗培养液吸出常规固定。两者均进行抗Cx43或抗Cx32的免疫荧光染色，Confoeal显微镜观察。结果第1组，Cx43在刺激1min后在星形胶质细胞表达比对照组有所增加，3min达到高峰，以后逐渐降低，15min恢复正常；而Cx32在刺激后1min的神经元中表达比对照组增加，5min达到高峰，以后降低。15min恢复正常。第2组同样为Cx43在星形胶质细胞刺激1min后表达增加，3min达到高峰，以后降低，10min恢复正常；神经元的Cx32表达在刺激后5min达到高峰，以后降低，10min恢复正常。两组Cx43表达的高峰期均早于Cx32。结论Cx43和Cx32可能参与星形胶质细胞与神经元渗透压的调节。

THE EFFECTS OF OSMOTIC PRESSURE CHANGING ON CONNEXINS EXPRESSION IN CULTURED RAT HYPOTHALAMIC ASTROCYTES AND NEURONS

Objective To investigate the effects of osmotic pressure changing on connexin43 (Cx43) and Cx32 expression in cultured rat hypothalamic astrocytes and neurons. Methods By culturing astrocytes and neurons from newborn rats,these cells were divided to two groups.The cells in first group were moved from isotonic culture medium to hypertonic culture medium and incubated for 1,3,5,10 and 15 min respectively,then,fixed by 4% paraformaldehyde.The cells in second group were moved from hypertonic culture medium to isotonic culture medium and incubated for 1,3,5 and 10 min respectively,they were fixed too.These cells were stained by anti-Cx43 or anti-Cx32 immunofluorescent method and observed under confocal microscope. Results In first group,the expression of Cx43 increased then incubation for 1 min,at 3 min peaked,then decreased,at 15 min backed to normal level.The expression of Cx32 peaked at 5 min,later decreased,at 15 min backed to normal level.In second group,the expression of Cx43 also increased after incubation for 1 min,at 3 min peaked,then decreased,at 10 min backed to normal level.Cx32 expression peaked at 5 min,then decreased,at 10 min backed to normal level.The peak of Cx43 expression was early than that of Cx32.Conclusion Cx43 and Cx32 might be involved in osmoregulation.