Influence of Maternal Nutrient Intake on Placental Vascular Function in Pregnant Beef Cows

We hypothesized that global maternal nutrient restriction during early and mid-gestation followed by realimentation in pregnant beef cows would alter placental arterial vascular function. We tested changes in placental caruncular (CAR) and cotyledonary (COT) arterial sensitivity to bradykinin (BK), a potent vasodilator. Cows were randomly assigned to be nutrient restricted for 55 or 110 during early to mid pregnancy. On d 85, 140, and 254 cows were euthanized and CAR and COT arteries were isolated. Maternal nutrient restriction during early and mid-gestation allowed for placental compensation to overcome the loss of nutrients while realimentation returned placental arterial vosoactivity similar to control cows in response to BK. Further, CAR and COT placental arteries may respond to BK induced vasodilation through different pathways which is important when considering possible therapeutics for compromised pregnancies