Evidence for Increased Content of PGF2α, PGE2, and 6-keto-PGF1α in Endometrial Tissue Cultures From Heavy Draft Mares in Anestrus With Endometritis

Abstract Endometritis is one of the most important causes of infertility in mares. Mares may suffer from endometritis outside the breeding season; however, pathological condition is often undiagnosed in anestrus. The aim of this study was to examine whether the secretion profiles of prostaglandin F 2α (PGF 2α ), prostaglandin E 2 (PGE 2 ), and a metabolite of prostacyclin I 2 (6-keto-PGF 1α ) differ in endometrial tissue cultures of heavy draft mares in anestrus with endometritis compared to those without endometritis. The endometrial biopsies were collected from 51 heavy draft mares. Inclusion criteria for the control group were absence of endometritis confirmed by histology and no ovarian activity. Inclusion criteria for the experimental group were presence of endometritis showing polymorphonuclear cells and/or lymphocytes infiltration in endometrium and no ovarian activity. Retrospectively, 22 mares were enrolled in this study. The content of PGF 2α ( P 2 ( P 2α synthase (PGFS; P 2 synthase (PGES; P P 1α ( P 1α was not significantly different between experimental and control groups. This leads to the conclusion that augmented endometrial secretion of PGF 2α , PGE 2 , and 6-keto-PGF 1α is associated with endometritis even in mares in anestrus.