Modulation of vascular reactivity after acute calcium antagonist administration in pregnant women moderately sensitive to angiotensin infusion.

Intracellular calcium is hypothesized to mediate vascular reactivity to infused angiotensin in pregnancy, which is increased in women at risk for subsequent development of gestational hypertension or preeclampsia. We infused scalar doses of angiotensin II in pregnant women at risk for hypertension and observed the possible modulation of vascular responsiveness after the administration of a calcium antagonist, in 38 women sensitive to moderate doses (greater than 10 and lower than 64 ng/kg/min). Results were correlated to perinatal outcome. Women moderately sensitive to angiotensin, in which an enhancement of the effective pressor dose after calcium antagonist administration occurred, showed a significant increase of bad perinatal outcomes. The modulation of the pressor test to infused angiotensin by calcium antagonist administration would reveal an activation of intracellular free calcium, and may be used as a second-line screening test.