RESUMEN
Prostaglandins (PGs) are the key mediators of several female reproductive functions, including luteolysis, ovulation, fertilization, implantation, pregnancy, and parturition. The present study was conducted in buffalo endometrial and luteal tissues between nonpregnant and two stages of pregnancy (29-38 days of pregnancy, 48-56 days of pregnancy) tissue samples. The genes involved from synthesis upto receptor level effect of PGs (PGF2α and PGE2) were studied for their relative mRNA expression. We have collected the endometrial and luteal tissues from slaughtered animals and confirmed the stages by external examination and crown vertebral rump length measurement of the foetus. The mRNA expression of COX-2 and PGFS genes revealed high significant rise in the transcript at pregnancy stage I as compared to the late luteal phase of nonpregnant. However, EP2 and EP3 genes were highly upregulated in pregnancy stage II. The expression of PLA2G4A and PGT genes showed difference in their transcripts in pregnancy, however, the difference was nonsignificant as compared to the nonpregnant stage. The findings emerged from this study also suggested the strict regulation at COX-2 mRNA level than at synthase enzyme's level. Among the four subtypes of EP gene, we have observed highly significant expression difference in EP2 followed by EP3 after implantation.