Expression of Vascular Endothelial Growth Factor A and Its Receptor FLT-1 in Canine Placenta

Introduction

Vascular endothelial growth factor A (VEGFA) and its receptor Flt-1 have been studied extensively in primate placentas, where they have been proposed to play a role in trophoblast invasion. In addition, placental Flt-1 mRNA expression has been shown to increase at term in humans. No studies have investigated the expression of these factors in the canine placenta at the time of parturition. Dysregulation of these factors could, for example, contribute to abnormal post-partum subinvolution of placental sites. Therefore, the aim of this study was to examine VEGFA and Flt-1 mRNA expression in canine chorio-allantoic tissue at pre-term, pre-labor and during parturition. The hypothesis was that expression of VEGFA and Flt-1 will be greater in term (pre-labor or parturient) than in pre-term bitches. [...]