Abstract: Abstract: Objective To investigate the therapeutic effect of mechanical loading on thin endometrium in model rat Methods Thirty female Sprague-Dawley (SD) rats were divided randomly into sham operation group (Sham group), thi endometrium model group (TE group) and mechanical loading treatment group (TE+L group). There were ten rats in eac group. The TE model was established by injection of 95% ethanol into the uterine cavity in the estrus phase. Normal salin was injected into the uterine cavity in Sham group. Rats of TE+L group received mechanical loading on the second day afte modeling. Loading force was 5 N and the frequency was 15 Hz for 5 min/day for 15 days. HE staining was used to observe th morphological changes of endometrium. The endometrial thickness, endometrial area and gland numbers were measured. Th expressions of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (Ki-67) were evaluated b immunohistochemistry. Results Uterine histological analysis showed that endometrial thickness, endometrial area an gland numbers were significantly decreased in TE group compared with those of Sham group (P＜0.05). Compared with T group, endometrial thickness, endometrial area and gland numbers were significantly increased in TE+L group (P＜0.05 Immunohistochemistry analysis indicated that the expressions of VEGF and Ki-67 were significantly lower in th endometrium of TE group than those of Sham group P＜0.05). After mechanical loading treatment, the expressions of VEG and Ki-67 were significantly increased in the endometrium of TE+L group (P＜0.05). Conclusion Mechanical loading ca effectively repair thin endometrium in rats, which may be related to the promotion of cell proliferation and angiogenesis o endometrium.

Key words: endometrium, vascular endothelial growth factors;, Ki-67 antigen, thin endometrium, mechanical loading, endometrial repair