The Effects of Micronized Progesterone and Cabergoline On a Rat Autotransplantation Endometriosis Model: A Placebo Controlled Randomized Trial

Abstract

Aim The etiology of endometriosis is complex and various theories have been postulated. Endometriosis pathogenesis involves genetic susceptibility, immunologic alterations and inflammatory prerequisite pathways. In this pilot experimental animal study we wanted to investigate the effects of cabergoline and micronized progesterone on a rat endometriosis model. Material and methods All rats were provided and housed in the animal laboratory of the Experimental Research Center of Bezmialem Vakif University. This was a placebo controlled randomized trial. The endometriosis model consisted of autotransplantation of endometrial tissue on 21 adult Sprague-Dawley rats. Endometriosis formation by second-look laparotomy was confirmed 8 weeks later. After measuring the endometriosis implant area the rats were randomized into three intervention groups: cabergoline treatment group, micronized progesterone treatment group and the control group. Four weeks after treatment, a third laparotomy was performed to remeasure implant volumes. Endometriotic implants were obtained for histopathological and immunohistochemical analysis. Results After 4 weeks of treatment endometriosis implant sizes diminished in all groups. There was no statistically significant difference regarding implant size volume before and after treatment among the groups. The peritoneal histopathology and immunohistochemistry showed no difference with regards to IL-6 and TNF-α staining among groups. Conclusion We conclude that oral treatment of cabergoline and micronized progesterone for 4 weeks was not statistically effective in endometriotic implant regression. However, we believe further studies are warranted. Treatment for longer durations or via different routes may be investigated in further studies. When ethically applicable other mammals may be considered such as baboons.