ALTERATIONS OF SEROTONIN METABOLISM IN PR EECLAMPSIA

Several complications of pregnancy have been reported to be associated with alterations of serotonin (5-HT). This study describes the change s in 5-HT metabolism in patients with preeclampsia. Our examination fi ndings should explain if there are elevated 5-HT and 5-HIAA concentrat ions in urine and serum of women with preeclampsia. On the other hand it should be proved if the observed chances are due to a decreased kid ney function and if there is an important prognostic factor to detect asymptomatic preeclamptic patients. 5-HT and its main metabolite 5-hyd roxy-indol-acetic acid (5-HIAA) was evaluated in serum and urine of 24 pregnant women with preeclampsia and of 27 pregnant women without pre eclampsia in the last month of pregnancy, within 24 hours after delive ry and at the fourth day post partum. Besides 5-HIAA was ascertained i n 24-h urine from the 24 th week of pregnancy until after delivery. 5- HIAA excretion increased continuously during pregnancy independently o f whether the patients developed preeclampsia. A significant less incr ease and lower concentration of 5-HIAA pre and post partum were observ ed in preeclamptic patients when compared to non-preeclamptic patients . We noticed a remarkably lower 5-HIAA excretion and a higher concentr ation of 5-HT in women with preeclampsia. Preeclamptic patients demons trate a lower decrease of 5-HIAA and a significantly greater increase of 5-HT than women without preeclampsia. These results could be explai ned by a decreased metabolism of 5-HT due to the placental MAO. The ch anges observed in our study are not due to a decreased kidney function because creatinine concentrations in women with and without preeclamp sia were comparable. Our results indicate that 5-HIAA-/creatinine rati o might be an important prognostic factor.