Intracellular and extracellular antioxidant buffering levels in erythrocytes from pregnancy-induced hypertension

Both intracellular (lysate thiol, lysate glutathione and lysate superoxide dismutase) and extracellular (plasma thiol, plasma glutathione and membrane thiol) antioxidant buffering levels were measured in red blood cells from patients with pregnancy-induced hypertension (PIH). We found the following. (1) The levels of plasma thiol and plasma glutathione in PIH women with proteinuria were markedly lower than that in the normal pregnancy. (2) The concentrations of lysate glutathione and superoxide dismutase in PIH women with proteinuria were significantly decreased compared with that in the normal pregnancy. (3) With the exception of plasma and lysate glutathione, all the tested antioxidant markers were not significantly different between PIH women without proteinuria and normal pregnancy. (4) There was no statistical correlation between antioxidant buffering level and BP in patients with PIH. We concluded that both extracellular and intracellular antioxidant buffering levels were decreased in patients with PIH, especially in those with proteinuria. The reduction of the antioxidant buffering level could account for several important pathophysiological features of PIH, such as the elevation of intracellular calcium, decreased red blood cell deformability and endothelial damage.