The Expressions of oestrogen receptors alpha and progesterone receptors in the cervix of Dogs undergone open-and closed-cervix pyometra

Abstract

The aims of the study were to investigate the immunolocalizations of oestrogen receptors alpha (ERα) and progesterone receptors (PR) in different cervical tissue compartment of dog undergone open and closed-cervix pyometra, to study histopathology of the cervix in open and closed-cervix pyometra and to evaluate the correlation between serum ovarian steroid hormones levels and the expression of ERα and PR. Cervical tissues samples were collected from 49 bitches, cervical tissues at anoestrus stage were represented as control group (n=8), pyometra was divided into two groups; open-cervix pyometra (characterized by the presence of a vaginal discharge) (n=22) and closed-cervix pyometra (n=19). The samples were fixed in 4% paraformaldehyde, embedded in paraffin and immunohistochemical stained for ERα and PR by avidin-biotin-peroxidase complex (ABC) method. The total ERα scores in the cervical tissues in all compartments in open-cervix pyometra and closed-cervix pyometra groups were not significantly difference. The significant difference of total ERα score was found between pyometra and the control groups. The ERα total scores in open-cervix pyometra group tended to be higher than in closed-cervix pyometra group but they were not significantly difference. The total PR scores in the cervical tissues in most compartments were not shown significantly different between groups, except in the surface epithelium of the cervix that total PR score in closed-cervix pyometra was significantly higher than open-cervix pyometra. From this present study, oestrogen and progesterone receptors may not involve in the difference of cervical characteristic in canine pyometra, however the other factors in cooperation with the steroid hormone may involve in the difference of cervical characteristic in canine pyometra.