气管干细胞分化过程中Shh信号通路的动态观察

目的:探讨大鼠气管上皮损伤后,气管干细胞增殖分化过程中Shh信号通路的动态变化.方法:应用5-氟尿嘧啶(5-FU)诱发气管上皮损伤,通过RT-PCR检测气管上皮Shh的表达.结果:5-FU作用30 min后大鼠气管上皮细胞绝大部分脱落,仅残留少量裸核样G0期细胞位于基底膜上.之后细胞数目逐渐增多,经过扁平、立方形态,向纤毛细胞、黏液细胞、基底细胞等分化,去除5-FU后48 h接近恢复假复层纤毛柱状上皮;正常气管上皮及5-FU作用30 min气管上皮Shh无表达,去除5-FU恢复3 h后Shh轻度表达,6 h后表达增强,12 h达高峰,之后表达减弱,48 h已极微弱.结论:Shh参与了气管干细胞的增殖分化过程.

Dynamic changes of sonic hedgehog signaling pathway during tracheal stem cell differentiation

Objective: To study the dynamic changes of sonic hedgehog(Shh) signaling pathway during tracheal stem cell differentiation after tracheal epithelial injury in rats.Methods:The tracheal epithelial injury was induced by 5-fluorouracil(5-FU).The expression of Shh in the tracheal epithelium was detected by RT-PCR.Results:Most tracheal epithelial cells exfoliated 30 minutes after the application of 5-FU,and a few stripped nucleus-like cells were randomly distributed on the basement membrane.The number of cells on the basement membrane increased gradually after 5-FU was removed,and the squamous and columnar epithelial cells differentiated into ciliated,mucosal,and basal cells.The epithelial cells differentiated into pseudostratified ciliated columnar epithelial cells 48 hours after 5-FU was removed.There was no expression of Shh in normal epithelium and injured epithelium 30 minutes after the application of 5-FU.The expression of Shh occurred gradually 3 hours after 5-FU was removed,increased 6 hours later,and reached the peak 12 hours later.Then the expression of Shh decreased and was faint 48 hours later.Conclusion:Shh may be involved in the proliferation and differentiation of tracheal stem cells.