Endometrial expression of estrogen and progesterone receptors in non-cyclic mares treated only with long-acting progesterone

Author(s)

Maciel, L. F. S. ^[1] ; Silva, E. S. M. ^[2] ; Oliveira-Filho, J. P. ^[3] ; Fritsch, S. C. ^[1] ; Rossi, R. S. ^[4] ; Lourencao, J. A. C. ^[1] ; Meira, C. ^[1]

Affiliation

^[1] UNESP Univ Estadual Paulista, Dept Anim Reprod & Vet Radiol, Sch Vet Med & Anim Sci, Campus Botucatu, BR-18618970 Botucatu, SP - Brazil

^[2] UNITRI Ctr Univ Triangulo, BR-38411106 Uberlandia, MG - Brazil

^[3] UNESP Univ Estadual Paulista, Dept Vet Clin Sci, Sch Vet Med & Anim Sci, Campus Botucatu, BR-18618970 Botucatu, SP - Brazil

^[4] UNESP Univ Estadual Paulista, Dept Vet Hyg & Publ Hlth, Sch Vet Med & Anim Sci, Campus Botucatu, BR-18618970 Botucatu, SP - Brazil

• Document type: Journal article
• Source: Theriogenology; v. 108, p. 185-191, MAR 1 2018.
• Web of Science Citations: 1

Abstract

Administration of progesterone (P4) after estradiol is usually performed to prepare non-cyclic mares as embryo recipients. However, there are successful pregnancy reports after embryo transfer in non-cyclic mares treated only with progestins. The objective of this study was to evaluate endometrial gene expression and immunostaining for estrogen receptor alpha (ER alpha), beta (ER beta) and progesterone receptor (PR) in seasonal anestrous mares treated with long acting P4 (LA P4). Endometrial tissue from eight seasonal anestrous mares was collected immediately before administration of 1.5 g of LA P4 and five days after. The receptors protein expression was evaluated by immunohistochemistry and the percentage of the immunostained area was determined by Image) software. Transcripts abundance for ER alpha, ER beta and PR were determined by RT-OCR. Blood samples were collected daily to measure plasma P4 concentrations. Protein expression for ER alpha was greater (p < 0.05) after LA P4 administration, although gene expression was not affected by treatment (p > 0.05). There was no difference for ER beta protein expression (p = 0.07) and ER beta gene expression was reduced (p < 0.05) after treatment. Gene and protein expression for PR was not altered (p > 0.05). In conclusion, endometrial PR and ER alpha expression patterns after LA P4 administration were similar to those previously found in protocols using estradiol prior to LA P4 to prepare non-cyclic mares as embryo recipients. (C) 2017 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 12/00298-7 - Qualitative and quantitative evaluation of estrogen and progesterone receptors in non-cyclic mares treated with estradiol benzoate and Altrenogest
• Grantee: Elisa Sant'Anna Monteiro da Silva
• Support Opportunities: Scholarships in Brazil - Doctorate