[Expression of occludin and zona occluden-1 and their morphologic changes in vagina mucosal cells in patients undergoing vaginal construction by using sigmoid colon].

Objective: In order to evaluate the changes of neovaginal defense function in the sight of physical barrier by investigating the changes in the histological morphology and expression of occludin, zona occluden-1 (ZO-1) in mucosal cells of the neovagina in patients undergoing vaginal construction by sigmoid colon.

Methods: Fifteen cases with neovagina constructed by sigmoid colon matched with 15 cases' vaginal mocusa as control specimens were observed with light microscopic and electron microscopic methods. At the same time, the expression of occludin and ZO-1 were semiquantitatively measured by streptavidin-perosidase (SP) immunohistochemical method.

Results: (1) Squamous metaplasia was observed in colonic mucosa from lower one-third of the artificial vagina in 10 cases (67%, 10/15). (2) The intercellular tight junctions of neovaginal mucosa became shorter and wider, the number of them were decreased or disappeared by electron microscopic study. (3) In upper neovagina, the positive rates of occludin and ZO-1 expression in mucosal cells were 80% (12/15) and 73% (11/15), respectively. In lower neovaginal mucosa where squamous metaplasia occurred, the positive rates of two protein expression in cells were both 100% (10/10) and also was 100% (15/15) in control group, which showed significant difference (P < 0.05, P < 0.01). In lower neovaginal mucosa where squamous metaplasia hadn't occurred, the positive expression of two protein in cells (4/5, 2/5) were significantly lower than those in lower neovaginal mucosa where squamous metaplasia had happened 100% (10/10), 100% (10/10) and in control group [100% (15/15), 100% (15/15)] (P < 0.05), while there were no significantly difference in positive expression of two protein in cells between this group and upper neovagina (P > 0.05).

Conclusions: The squamous metaplasia had occurred in lower neovaginal mucosa. The decreased expression of occludin and ZO-1 in upper and lower neovaginal mucosa where squamous metaplasia didn't occurred. However, In lower neovaginal mucosa where squamous metaplasia occurred, the expression of occludin and ZO-1 in cells were similar to those in control group, which might play a role in the defense function of neovaginal mucosa.