pathological evaluation of the rat endometriosis model objective to observe in detail the morphology of experimental rat endometriosis specifically in peritoneum adjacent to uterine transplants attached via autotransplantationdesign light and electron microscopic studysetting tochigi institute of clinical pathology japananimals femalesd rats maintained on a schedule of 12 hours of light and 12 hours of dark for 2 weeksinterventions uterine transplants were attached to rat peritoneum via the surgical autotransplantation technique the implanted area of peritoneum including abdominal muscle were excised from anesthetized rats at four n 10 seven n 10 and 14 n 10 days after uterine autotransplantation the mesenteries were autotransplanted as a comparative controlmain outcome measures we examined the morphologic alterations of uterusattached peritoneum following the time interval after the implantationresults in rat endometriosis models the stromal tissue of uterusattached peritoneum showed proliferation and infiltration of mast cells eosinophils plasma cells lymphocytes and macrophages these lesions increased with time after implantation however ultimately these infiltrating cells disappeared and proliferation declinedconclusions our findings suggest that uterine autotransplantation induces the infiltration of allergic inflammatoryrelated cells and proliferative lesions in peritoneal stroma attached endometrium these data should prove useful for investigations of human endometriosis