Study of the mechanism of action for wich estradiol stimulates PGF2a endometrial synthesis in female bovine

• Grant number: 14/08815-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2014
• End date: June 30, 2015
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Claudia Maria Bertan Membrive
• Grantee: Bruna Folegatti Santana
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental de Dracena. Dracena , SP, Brazil

Abstract

In bovine females release of PGF2a can be induced in vivo by estradiol (E2), however, the role of E2 in the synthesis of PGF2a has not yet been clarified. Whereas the increase plasma concentrations of PGF2 3.5 hours after the application of E2 in vivo, it is believed that E2 activates not only enzymes, but also stimulates the synthesis of proteins essential for the production of PGF2a. It is known that bovine endometrial explants from animals injected with E2, and cultivation of bovine endometrial cells (BEND) exposed to E2, to be treated with calcium ionophore (CI) had a marked increase in the release of PGF2a compared with those who did not received E2 and E2 treated exclusively with or CI. The hypothesis is that E2 stimulates the expression and/or activity of PKC and PLA2 enzymes, both calcium -dependent activation, involved in the synthesis of endometrial PGF2a. The hypothesis is that E2 stimulates the expression and/or activity of PKC and PLA2 enzymes, both calcium -dependent activation, involved in the synthesis of endometrial PGF2a. The aim of this study is to identify groups of genes involved in the synthesis of endometrial PGF2a in bovine females, whose expression is modulated by E2 by RT - qPCR and further substantiate the different proteins identified as in experiment 2 by Western blotting. Cyclical Nellore females ( n = 60 ) , non-lactating , will be paired on the 17th of a synchronized estrous cycle , injected with 0 mg ( n = 30 ) or 17² - estradiol 3mg ( n = 30 ) and then be subdivided within each group to have a uterine biopsy of the uterine horn ipsilateral to the corpus luteum performed 2 hours ( n = 6 n = 6 0 mg to 3 mg de17² -estradiol ) or 3 hours (n = 6 n = 6 0 mg to 3 mg de17² - estradiol) or 4 hours (n = 6 n = 6 0 mg to 3 mg de17² - estradiol) or 5 hours (n = 6 n = 6 0 mg to 3 mg de17² -estradiol ) or 6 hours (n = 6 n = 6 0 mg to 3 mg de17² - estradiol) . Tissue samples will be evaluated for mRNA expression by RT- qPCR for specific proteins involved in the synthesis of endometrial PGF2 , among these aldo - keto redutase1B1 , Aldo - keto reductase 1C3, oxytocin receptor, phospholipase A24A , PKC± , PKC² , PKC³ , cyclooxygenase 1 and cyclooxygenase 2.