Qualitative and quantitative evaluation of estrogen and progesterone receptors in non-cyclic mares treated with estradiol benzoate and Altrenogest

• Grant number: 12/00298-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: March 01, 2012
• End date: June 30, 2015
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Cezinande de Meira
• Grantee: Elisa Sant'Anna Monteiro da Silva
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated scholarship(s): 14/08207-6 - Effect of dose and administration frequency of estradiol benzoate on estrogen plasma concentration in non-cyclic embryo recipient mares, BE.EP.DR

Abstract

Estrogens and progestins protocols are usually applied in equine embryo transfer programs in order to establish pregnancy in non-cyclic mares. Currently, estradiol is applied to acyclic recipient mares and after observation of uterine edema, progesterone or altrenogest is administered during 4 to 8 days. Administration of estradiol prior to progestins is based on cyclic mares researches, where estrous estrogen stimulates their own receptors expression and expression of progesterone receptors. On the other hand, progesterone causes endometrial changes that allow pregnancy establishment and maintenance. In addition, leads to reduction of estrogen and progesterone receptors during diestrous in cyclic mares. Little is known about estrogen and progesterone endometrial receptors in non-cyclic mares and, moreover, there are no researches that describe the effects of steroid administration on endometrial estrogen and progesterone receptors to non-cyclic recipient mares used in embryo transfer programs. The aim of the present study is to evaluate and compare the effect of estradiol and progesterone administration on expression and detection of estrogen and progesterone endometrial receptors in anestrous and transitional recipients. The same mares will be evaluated (n=12), in three different groups (anestrous, transitional and cyclic mares), through rectal palpation, ultrasonography and biopsy collection for receptor research using immunohistochemistry and RT-qPCR techniques. Steroidal receptors research will enable description and evaluation of possible differences on expression and detection of endometrial estrogen and progesterone receptors in anestrous and transitional mares, submitted to an estrogen and progesterone protocol applied in embryo transfer programs. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SILVA, E. S. M.; IGNACIO, F. S.; FRITSCH, S. C.; ZANONI, D. S.; PANTOJA, J. C. F.; OLIVEIRA-FILHO, J. P.; MEIRA, C.. Administration of 2.5 mg of estradiol followed by 1,500 mg of progesterone to anovulatory mares promote similar uterine morphology, hormone concentrations and molecular dynamics to those observed in cyclic mares. Theriogenology, v. 97, p. 159-169, JUL 15 2017. (12/00298-7)

MACIEL, L. F. S.; SILVA, E. S. M.; OLIVEIRA-FILHO, J. P.; FRITSCH, S. C.; ROSSI, R. S.; LOURENCAO, J. A. C.; MEIRA, C.. Endometrial expression of estrogen and progesterone receptors in non-cyclic mares treated only with long-acting progesterone. Theriogenology, v. 108, p. 185-191, MAR 1 2018. (12/00298-7)

SILVA, ELISA S. M.; LEITE, RAISSA O.; MACIEL, LUCIANA F. S.; FRANCIA, CAMILA C. D. A.; PADOVANI, CARLOS R.; OLIVEIRA-FILHO, JOSE P.; MEIRA, CEZINANDE. Endometrial Histomorphometry of Anestrous Mares Under the Influence of Different Embryo Transfer Hormonal Protocols. Journal of Equine Veterinary Science, v. 81, OCT 2019. (12/00298-7)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

SILVA, Elisa Sant'Anna Monteiro da. Effect of estradiol and progesterone administration on hormonal concentrations and endometrial expression of estrogen and progesterone receptors in non-cyclic recipient mares. 2015. Doctoral Thesis - Universidade Estadual Paulista (Unesp). Faculdade de Medicina Veterinária e Zootecnia. Botucatu Botucatu.