The calcium-dependent nitric oxide production of human vascular endothelial cells in preeclampsia.

Abstract

Nitric oxide is an important vasodilator, and in this study we studied whether the calcium-dependent nitric oxide production capacity of human umbilical vein endothelial cells was affected by preeclampsia. Human umbilical vein endothelial cells were isolated from 11 preeclamptic and 10 normotensive pregnancies. The maximal calcium ionophore A23187-stimulated nitric oxide production capacity was measured as accumulation of nitrate and nitrite into the culture medium, and it was related to the number of viable endothelial cells by measurement of their mitochondrial dehydrogenase activity. The cell number-related nitric oxide production capacity was similar in preeclamptic and normotensive pregnancies. The total nitric oxide production of cells from preeclamptic pregnancies was significantly lower (p <0.001). This difference, however, was mainly caused by larger amount of viable endothelial cells recovered from normotensive pregnancies. The maximal calcium-dependent nitric oxide production capacity of individual human umbilical vein endothelial cells is not affected by preeclampsia.