title: Changes in ovaries and uterus after aglepristone administration in the third week of luteal phase of non-pregnant bitches.
abstract: OBJECTIVE
  The mechanism of aglepristone action in the placentation time in the bitch remains unclear. The aim of this study was to describe the mechanism by which aglepristone influences ovaries and uterus and to measure the levels of steroid sex hormones in non-pregnant bitches.
  
  
  METHODS
  Fourteen bitches assigned to a study (n=9) and control (n=5) group were given aglepristone and saline solution, respectively, on the 19th and 20th day after LH peak. On the 26th day after LH peak an ovariohysterectomy was performed. Blood samples were screened for estradiol and progesterone concentrations. Ovaries and uterine horns and bodies were isolated for histological and morphometrical diagnosis and immunohistochemistry analysis of α-estrogen and progesterone receptor expression.
  
  
  RESULTS
  A decrease of progesterone (p<0.01) and no differences in total estrogen level in the study group were observed. There were no significant differences either in the histomorphometry or α-estrogen and progesterone receptors expression in ovaries. Increase in expression of progesterone receptors in endometrium without surface epithelium of horns (p<0.05), endometrial surface epithelium (p<0.05), myometrium of uterine body (p<0.01) and estrogen receptors in endometrium without surface epithelium of horns (p<0.05) was observed. Elevated estrogen receptors probably increased sensitivity of tissues to estrogens in the bloodstream and led to notable inflammation, haemorrhages, and hyperplasia in endometrium with mononuclear immune cell infiltration. The myometrium of horns and endometrium of uterine body of study bitches were significantly thicker than in the control group (p<0.05 and p<0.01). Furthermore myometrium of uterine body was thicker than myometrium of horns (p<0.001) and expression of progesterone receptors was higher in uterine body (p<0.01). No differences were observed between endometrium of horns and body within groups.
  
  
  CONCLUSIONS
  To the knowledge of the authors this is the first study, which describes the inflammatory effect developing in uterus in response to aglepristone administration, and attempts to elucidate its mechanisms.
authors: Department of Small Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors: Kamil
authors: K
authors: Kacprzak
authors: Department of Small Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors: Piotr
authors: P
authors: Jurka
authors: Department of Pathology and Veterinary Diagnostics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors: Izabella
authors: I
authors: Dolka
authors: Laboratory of Veterinary Epidemiology and Economics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors: Michał
authors: M
authors: Czopowicz
authors: Department of Small Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors: Anna
authors: A
authors: Ruszczak
authors: Department of Morphological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors: Anna
authors: A
authors: Duszewska
mesh_terms: D000818:Animals; D004285:Dogs; D004958:Estradiol / Q000097:blood; D004963:Estrenes / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D007044:Hysterectomy / Q000662:veterinary; D007249:Inflammation / Q000209:etiology* / Q000473:pathology; D008183:Luteal Phase / Q000187:drug effects*; D010052:Ovariectomy / Q000662:veterinary; D010053:Ovary / Q000098:blood supply / Q000187:drug effects / Q000601:surgery*; D011374:Progesterone / Q000097:blood; D014599:Uterus / Q000098:blood supply / Q000187:drug effects / Q000601:surgery*
chemical_list: D004963:Estrenes; C419063:aglepristone; D011374:Progesterone; D004958:Estradiol