VASOACTIVE PEPTIDES AND UTERINE VESSELS

Endothelins and atrial natriuretic peptide (ANP) are vasoactive peptid es with effects on the human uterine and umbilical arteries. Endotheli n (ET) contracts the vascular smooth muscle. Both ET(A)- and non-ET(A) -non-ET(B)-receptors seem to be involved. Autoradiography reveals bind ing of ET to vascular smooth muscle. ANP counter-acts the contractile effects of angiotensin II in the human uterine artery. Head-down tilt results in elevation of plasma ANP in healthy pregnant women, while th e same manoeuvre induces down-regulation of the renin-angiotensin-aldo sterone system in non-pregnant women and patients suffering from pre-e clampsia.