POMC, iNOS, PGES, IL-4, IL-5 and IL-10 Gene Expression in Peripheral Blood Mononuclear Cells of Cyclic and Pregnant Mares

Although a number of different clinical and laboratory methods are used, there is still need for a practical, reliable and economical diagnosis method for early pregnancy in mares. Objective was to provide a preliminary background for understanding immunological modifications at molecular level during early pregnancy in mare and thereby to allow development of a practical pregnancy test. Blood samples were collected from 10 pregnant and 4 cyclic mares on days of ovulation (d0), 4 and 8. Total RNA samples were isolated from peripheral blood mononuclear cells (PBMC) and cDNA synthesis was performed. Pregnancy dependent gene expression profiles of proopiomelanocortin (POMC), nitric oxide synthase (iNOS), prostaglandin E synthase (PGES), interleukin-4 (IL-4), IL-5 and IL-10 were evaluated at mRNA level using semiquantitative Reverse Transcriptase-Polymerase Chain Reaction. Data were analyzed by General Linear Model and possible differences between all mean factors were determined by Tukey's analysis. No gene expressions were observed for PGES, IL-5 and iNOS in PMBCs. Expressions of POMC, IL-4 and IL-10 were not significant on d0, 4 and 8, which suggested that pregnancy or cyclic status had no effect on expression of these genes. Only, IL-10 mRNA expression was lower in pregnant mares than cyclic mares (P < 0.05).