[Thrombocyte prostacyclin receptors in gestational hypertension and pre-eclampsia].
OBJECTIVE: To determine prostacyclin (PGI2) receptor characteristics in pregnancies complicated by hypertension and to assess any relation to the clinical outcome. METHODS: Radioligand binding studies with [3H]-Iloprost were performed to measure receptor capacity (Bmax) and affinity (Kd-1) using platelet membranes from patients with preeclampsia, gestational hypertension or normal pregnancy. RESULTS: PGI2 receptor capacity did not differ between the patient groups. In contrast, PGI2 receptor affinity was diminished in gestational hypertension and considerably reduced in preeclampsia compared to normal pregnancy. A similar pattern was found in fetal growth (normal pregnancy > gestational hypertension > preeclampsia). Furthermore, the rate of low Apgar scores and acidosis was increased in preeclampsia. CONCLUSIONS: In preeclampsia reduced platelet PGI2 receptor affinity was found as well as poor pregnancy outcome in comparison with normal pregnancy, whereas these differences were less pronounced in gestational hypertension. This suggests a role of PGI2 and its receptor in gestational hypertension and in particular in preeclampsia.