Sensitivity to angiotensin II of forearm resistance vessels in pregnancy.
Resistance vessel sensitivity to angiotensin II in vivo was studied in 13 primigravid normotensive women (16-24 weeks gestation), and in 10 non-pregnant control women. Angiotensin II was infused into the brachial artery at doses of 10, 100, 1,000 and 10,000 fmol min-1 and forearm blood flow measured by plethysmography. Reduction in forearm blood flow at all concentrations of angiotensin II was significantly greater in non-pregnant than in pregnant women. The dose-response relationships, plotted semi-logarithmically, were similar in shape in each group but sensitivity to angiotensin II was reduced in pregnant subjects compared with non-pregnant women. This is most simply explained by an effect of pregnancy on the sensitivity to angiotensin II of vascular smooth muscle in forearm resistance vessels.
Benjamin
N
N
Department of Clinical Pharmacology, Guy's Hospital Campus, London Bridge.
Rymer
J
J
Todd
S D
SD
Thom
M
M
Ritter
J M
JM
D000328:Adult; D000804:Angiotensin II / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D005260:Female; D005542:Forearm / Q000098:blood supply; D006801:Humans; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D011247:Pregnancy / Q000502:physiology*; D012039:Regional Blood Flow / Q000187:drug effects
D000804:Angiotensin II