Abstract: Objective To investigate the expression of transforming growth factor-beta 1 in endometrial fibrosis in rats and related mechanisms. Methods Sprague-Dawley female rats were randomly divided into sham operation group (n=12) and model group (n=12). Uterine tissues were collected on days 7, 14 and 18 after surgery. HE staining and Masson staining were measured the number of endometrial glands and degree of endometrial fibrosis. The protein expression of TGF-β1 and α-SMA were measured by immunohistochemistry. Results Compared with the sham operation group, the uterine structure of the rats in the model group was significantly disrupted; there was a significant increase in TGF-β1 expression in the model group at 7 days,14 days, and 28 days of modeling; the number of endometrial glands decreased, the fibrotic area of endometrium increased and the expression of α-SMA was significantly higher at 14 days and 28 days of modeling. Conclusions TGF-β1 may promote endometrial fibrosis by activating myofibroblasts.

Key words: intrauterine adhesions, fibrosis, rat, TGF-β1, α-SMA