Effect of anti-TNF-α on peritoneal endometrial implants of rats.

OBJECTIVE To evaluate the effect of anti-TNF-α in the treatment of endometrial implants in the peritoneum of rats. METHODS Endometrial implants were surgically induced in 120 female Wistar-Albino rats. The animals were randomly divided into four groups. Group C (n = 36) received an intraperitoneal injection of 0.2 ml of saline. Group L (n = 41) received a subcutaneous injection of 1mg/kg of leuprolide. Group I5 (n = 20) received a subcutaneous injection of 5mg/kg of monoclonal anti-tumor necrosis factor (TNF) a (infliximab). Group I10 (n = 20) received a subcutaneous injection of 10mg/kg of infliximab. The rats were sacrificed after 21 days to assess the size of the implants and the expression of TNF. RESULTS Treatment with leuprolide (group L) promoted an absolute reduction in the surface area of the implant when compared with group C (+14 mm vs. 0mm, p = 0.013) and group I10 (+14 mm vs. +5 Mm, p = 0.018). Likewise, a percentage reduction of surface area of the implant was observed comparing group L with group C (+33.3% vs. 0%, p = 0.005) and group I10 (+33.3% vs. +18.3%, p = 0.027). Treatment with infliximab was not able to decrease the surface area of the implants when compared with group C. The expression of TNF-α in groups L, I5 and I10 was lower than in group C (505.6 mm(2) vs. 660.5 mm(2) vs. 317.2 mm(2) vs. 2519.3 mm(2), respectively; p <0.001). CONCLUSION The anti-TNF-α therapy reduced the expression of TNF-α in endometriotic implants, but did not reduce the surface area of the lesion.