Cloprostenol administration in the first week postpartum reduces expression of oxytocin receptors in the endometrium in Holstein-Zebu cows

A Camargos,J.C Ferreira,I.F Costa,A.A Ramos,L.S Camargo,E Oba,S Wohlres-Viana

doi:10.1590/1678-4162-9318

Abstract

ABSTRACT The present study investigated the hormonal profile and expression of prostaglandin F2α (PGF2α), oxytocin and estrogen receptors in uterine tissues of postpartum cows treated with cloprostenol. Twenty Holstein-Zebu crossbred cows were treated with saline solution (treatment CONT) or cloprostenol (treatment CLO), both administered two and five days postpartum. Blood samples were collected on days two, seven, 14, 21 and 28 postpartum for progesterone, PGF2α metabolite (PGFM) and estradiol determination, and endometrial biopsy was performed in order to quantify the expression of oxytocin receptor (OXTR), prostaglandin F receptor (PTGFR) and estrogen receptor 1 (ERS1) genes. In the CLO treatment, expression of OXTR was reduced (P<0.05) but no difference (P>0.05) between treatments was found for PTGFR and ERS1 expression. Estrogen concentrations increased progressively until day 14 (P<0.05) and the highest OXTR expression and lowest PTGFR expression were observed on day 14 (P<0.05) in both treatments. Serum PGFM concentrations were high throughout the experiment. In conclusion, cloprostenol administration at days two and five of postpartum seems to reduce OXTR expression in the endometrium in crossbred cows.

Highlights

Postpartum release of substantial amounts of prostaglandin F2α (PGF2α) matches the period of uterine involution (Kindahl et al, 1999)
The present study investigated if postpartum administration of the synthetic prostaglandin cloprostenol to crossbred cows: i) increases of plasmatic PGF2α metabolite (PGFM) do not affect progesterone and estradiol concentrations; and ii) increases PGF2α and expression of oxytocin receptor gene does not affect expression of estrogen receptor gene in uterus
Progesterone is continuously secreted by the corpus luteum and placenta, but secretion interruption during prepartum luteolysis lowers progesterone concentration drastically in the postpartum period

Summary

Introduction

Postpartum release of substantial amounts of prostaglandin F2α (PGF2α) matches the period of uterine involution (Kindahl et al, 1999). Report that an increase in serum PGF2α metabolite (PGFM) concentrations does not account for uterine involution (Nakao et al, 1997; Salasel and Mokhtari, 2011). Data on the association between the time PGFM remains at high concentrations and the time required for complete uterine involution are controversial (Nakao et al, 1997; Kindahl et al, 1999). Outcome data of prostaglandin-based protocols regarding the hormonal profile of crossbred cows in the postpartum period are not available (Salasel and Mokhtari, 2011; Haimerl et al, 2012)

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Results

Conclusion