Angiotensin II vascular smooth-muscle receptors are not down-regulated in near-term pregnant sheep.

摘要: Abstract Normal human and ovine pregnancies are associated with elevated plasma angiotensin II levels refractoriness to the vasoconstrictor effects of infused II, which is greater in uteroplacental vascular bed than systemic vasculature. It remains unclear whether this reflects alterations smooth-muscle receptor density or affinity. We examined nonpregnant ( n = 12) near-term pregnant (130 ± 3 days [mean SO], 1 0) sheep, comparing binding characteristics on membranes prepared from medial layer aorta, mesenteric artery, uterine artery. Plasma were increased threefold fourfold p