The ontogeny of kisspeptin receptor in the uterine contractions in rats: Its possible role in the quiescence of non-pregnant and pregnant uteri

The objectives of this study were to investigate the effects KISS1 94-121 fragment on contractility non-pregnant and pregnant rat uteri, determine uterine myometrial expressions Kiss1r. Uterine muscle strips obtained from Sprague-Dawley rats in oestrous phase gestational days 5, 15, 18, 20 or 22. vitro measurements carried out an isolated organ bath presence 94-121. Experiments with 5-day tissues also performed kisspeptin-234 trifluoroacetate. mRNA protein Kiss1r measured by RT-PCR Western blot analysis, while localizations receptors defined fluorescent immunohistochemistry. induced a dose-dependent relaxation both intact endometrium-denuded uteri. A gradual decrease was found towards end period, it further confirmed immunohistochemical results. significant majority is myometrium, however few endometrial influences contractions. relaxing effect kisspeptin continuously reduced period parallel reduction expression. Our results suggest putative role maintenance quiescence that may have significance miscarriage preterm