Endometriosis is defined as the growth of endometrium outside of the uterus in ectopic places. Immune system disturbances have an important role in endometriosis which may lead to infertility. It seems that inflammatory cytokines, specially tumor necrosis factor-alpha (TNF-α), which are produced by activated macrophages, play an important role in the pathology of endometriosis. Based on this theory, anti-TNF-α drugs are suggested as new drugs for endometriosis. This experimental study has been performed on female rats to determine the effect of pentoxifylline on the white blood cell count in serum and peritoneal fluid.Methods
During the proestrous phase, one horn of the bicorn uterus of rats was removed surgically, and the endometrium implanted to different places as follows: subcutaneous, peritoneum and near the ovaries. After 2 months' observation, female rats were divided randomly into two groups. The treated group (n = 10) were given pentoxifylline (5 mg/kg twice a day), and the control group (n = 10) were given normal saline (the same dose), which was injected subcutaneously. Then via second laparotomy and in the same phase of the cycles, the size of implants and the white blood cell levels in the serum and peritoneum were measured.Results
In the treated group, the total implant mass (mm2) decreased significantly in the right subcutaneous (8.05 mm2vs 13.5 mm2; P = 0.01), left subcutaneous (7.64 mm2vs 14.00 mm2; P = 0.01), right ovary (6.64 mm2vs 15.22 mm2; P = 0.001) and left ovary (7.18 mm2vs 14.56 mm2; P = 0.005). The total white blood cell count (5254.5455 ± 178.73 vs 15 833.33 ± 259.27; P = 0.02) and neutrophils (297.34 ± 57.34 vs 2736.00 ± 346.75; P = < 0.001) in the serum were decreased and the total count of lymphocytes (4967.92 ± 696.194 vs 13 048.33 ± 178.73; P = 0.003) in serum was increased. There were not any significant changes in the total white blood cell count in the peritoneum in both groups. The number of estrous cycles in both groups was similar.Conclusion
Based on our study, pentoxifylline could decrease the size of endometrial implants, especially in the ovaries and subcutaneous areas, and total white blood cell count in serum. Pentoxifylline could increase the lymphocyte count and decrease the neutrophil count in serum, and because these changes it might alter the immune system. Pentoxifylline did not have any adverse effect on rats' cycles and a good aspect of treatment with pentoxifylline was achieved.