Renin angiotensin aldosterone system and adrenergic system in normotensive and hypertensive pregnancy

We have measured simultaneously plasma renin activity (PRA), aldosterone and catecholamines in the plasma of 3 groups of pregnant women after the 20th week: group 1 of 16 normotensive controls, group II of 17 women with rest responding hypertension (RRH), group III of 18 women with permanent hypertension (PIH). All the patients were ambulatory on a normal salt diet. PRA was significantly higher in the RRH than in the control and PIH groups (15,8 +/- 2,3ng/ml/l versus 6,7 +/- 0,5 and 8,9 +/- 0,9 respectively). Plasma epinephrine (PE) and norepinephrine (PNE) were significantly higher in the PIH than in the control and RRH groups (respectively 135 +/- 28 pg/ml versus 56 +/- 13 and 63 +/- 17 for PE and 387 +/- 91 versus 206 +/- 32 and 200 +/- 47 pg/ml for PNE). In the PIH group there was a negative correlation between PRA and blood uric acid. It is concluded that the adrenic system is activated in PIH whereas the renin angiotensin system is activated in RRH of pregnancy.