Gestational hypertension plasma and human umbilical vein endothelial cells: an in vitro study

Background The action of plasma from women affected by gestational hyperten sion (GH) on nitric oxide synthase (NOS) activity in cultured human umbilic al vein endothelial cells (HUVECs) was evaluated in the present study, toge ther with the effect on cytosolic calcium, on Na+, K+-ATPase activity and o n membrane fluidity. Methods At 80% confluence, cultured HUVECs were incubated for 3 h at 37 deg rees C with fresh culture medium (control samples) or with 20% (v/v) plasma (from five healthy non-pregnant women, five healthy pregnant women and fiv e pregnant women affected by GH). Results After incubation with GH plasma, we observed a significant reductio n in NOS activity, intracellular calcium concentrations and Na+, Kt-ATPase activity. Conclusions The present work gives further support to the hypothesis that a circulating factor in gestational hypertension, possibly produced by the f etoplacental unit, causes dysfunction of the vascular endothelial cells and NO reduction, resulting in a loss of vascular refractoriness to vasoactive agents.