水通道蛋白5和细胞程序性死亡分子5在大鼠腮腺主导管结扎再通后表达的实验研究

Expression of Aquaporin 5 and Programmed Cell Death 5 in Rat Parotid Gland after Ligation and Recanalization

目的:研究大鼠腮腺在不同的导管结扎时间点再通后的再生能力,探讨水通道蛋白5(aquaporin 5,AQP5)和细胞程序性死亡分子5(programmed cell death 5,PDCD5)在腮腺再生过程中的作用。方法:结扎大鼠腮腺主导管,分别在结扎7d(A组)、结扎14d(B组)、结扎21d(C组)再通后取不同时间点(0、1、3、5、7、10、14、21、28d)腮腺标本,通过苏木素-伊红(hematoxylin and eosin stain,HE)染色观察腺体组织的形态变化,并通过免疫组织化学法、实时定量聚合酶链反应(real-time quantitative polymerase chain reaction,real-time PCR)等方法研究AQP5和PDCD5在腮腺中的表达规律。结果:腮腺主导管结扎再通后3组均出现腺体再生现象,结扎7d和14d组的腮腺再通后AQP5表达逐渐增多,可分别在再通后第14天和第21天恢复至正常水平,而结扎21d组,在再通28d后仍未能完全恢复。PDCD5在腺体再通后随导管的凋亡出现增高趋势,3组分别在再通后第5天、第10天、第14天达到最高水平,B组峰值最大,C组其次,A组峰值最小。结论:大鼠腮腺主导管结扎时间越久,其再生能力越差,AQP5的表达是腮腺组织功能恢复的重要指标,腺体再生过程中导管样结构发生凋亡。

Objective:To investigate the regenerating ability of parotid gland after different ligated time,and the effect of aquaporin 5(AQP5)and programmed cell death 5(PDCD5)on the regeneration of parotid gland in rats.Methods:The parotid gland was ligated and then reopened after 7 days(group A),14 days(group B),and 21 days(group C),respectively.The samples were obtained at different time points(0,1,3,5,7,10,14,21,and 28 days).The morphological changes of glandular tissue were observed by HE staining,and the expression patterns of AQP5 and PDCD5 in acinor cells and glandular cells were explored.Results:Gland regeneration occurred in three groups after the reopen of main duct of parotid gland.The expression of AQP5 could increase to the normal level after reopen 14 days and 21 days for group A and group B,however,not recover to the normal level even after 28 days for group C.Expression of PDCD5 increased with the increase of apoptosis of the duct after the gland release.The three groups reached the highest level respectively after the recanalization of fifth days,the tenth day,and the fourteenth day,the peak value of group B was the highest,group C was the second,and the peak value of group A was the lowest.Conclusions:The longer the time ligation of the main duct of rat parotid gland,the worse the ability of regeneration.The expression of AQP5 is an important marker of functional recovers of the gland.Apoptosis of ductal like structure happened during the gland regeneration.