[Study on platelet antioxidant enzyme activity and platelet granule membrane glycoprotein in patients with pregnancy induced hypertension]

To evaluate the platelet antioxidant enzyme activity and platelet activation degree in patients with pregnancy induced hypertension (PIH).

A monoclonal antibody specific for alpha-granule membrane protein (GMP-140) of platelet was used to evaluate the platelet (plt) activation degree in 44 cases with PIH and 28 cases of normal pregnant women. Meanwhile, the platelet antioxidant enzyme (superoxide dismutase, SOD; catalase, CAT) activity were determined.

Platelet SOD activity of PIH (22.08 +/- 7.66 U/10(9) plt) was markedly lower than that of the controls (26.67 +/- 7.59 U/10(9)plt, P < 0.01). There was no difference between the CAT activity of PIH and controls (9.26 +/- 4.53 K/10(12) plt, 8.57 +/- 3.69 K/10(12) plt, P > 0.05). The number of GMP-140 molecules on platelet surface and serum levels of PIH (2073 +/- 902 molecules/plt, 4.65 +/- 1.74 molecules/L x 10(-13) were significantly higher than those of the normal pregnant women (1319 +/- 716 molecules/plt, 1.69 +/- 0.78 molecules/L x 10(-12), P < 0.01). Correlation analysis between GMP-140 on platelet surface, GMP-140 in the serum and SOD activity of PIH showed definite negative correlation (r = -0.601, -0.670 respectively, P < 0.05).

The decline of platelet antioxidant enzyme activity (especially SOD) and platelet activation could play an important role in the pathophysiological changes in PIH. The platelet SOD activity and GMP-140 could be new index of platelet hyperactivity.