Endothelin-1 activity in pregnancy

Abstract

Plasma endothelin-1 activity was measured by radioimmunoassay in 24 normotensive non-pregnant women and in 24 normotensive pregnant, 24-aproteinuric hypertensive and 24 pre-eclamptic women. Endothelin-1 activity was increased in the pre-eclamptic group (2·7 - 06 pg/ml) compared to the normotensive non-pregnant (1·0 - 0·8 pg/ml; P < 0·0001), normotensive pregnant (1·2 - 0·4 pg/ml; P < 0·0001) group and the aproteinuric hypertensive group (1·4 - 0·7 pg/ml; P < 0·0001). There was no difference in endothelin-1 activity between the normotensive non-pregnant and normotensive pregnant group (1·0 - 0·8 vs. 1·2 - 0·4 pg/ml; P = 0·3). However, there was a difference between the aproteinuric hypertensive group (1·4 - 0·7 pg/ml) and both the normotensive non-pregnant (1·0 - 0·8 pg/ml; P < 0·01) and the normotensive pregnant group (1·2 - 0·4 pg/ml; P < 0·06). The birth weight in the pre-eclamptic group (2·48 - 0·61kg) was significantly lower than that of the normotensive pregnant group (2·85 - 0·33 kg ; P < 0·001) and the aproteinuric hypertensive group (2·99 - 0·46 kg; P < 0·001). In addition, there was no difference in birth weight between the normotensive pregnant group and aproteinuric hypertensive group (2·85 - 0·33 vs. 2·99 - 0·46 kg; P = 0·3). A significant Pearson's correlation of plasma endothelin-l versus birth weight in the pre-eclamptic group was obtained ( r = 0·64; P < 0·0001). Endothelin-1 activity is increased with pre-eclampsia in black African women with pre-eclampsia. The results of our study also suggests an ethnic difference in plasma endothelin-1 activity when compared to result of studies carried out in Caucasian women with hypertensive disorders of pregnancy.