DECREASE IN CYTOCHROME-C-OXIDASE ACTIVITY DETECTED CYTOCHEMICALLY IN THE PLACENTAL TROPHOBLAST OF PATIENTS WITH PREECLAMPSIA

This study was designed to explore the possible relationship between c ytochemically detectable cytochrome c oxidase (COX) activity in the tr ophoblast and placental dysfunction in patients with pre-eclampsia. Fi fteen placentae (10 from women with an uncomplicated pregnancy and fiv e from patients with pre-eclampsia) were involved in this study. Local ization of COX activity in the placental trophoblast was determined by ultrastructural enzyme cytochemistry using DAB as a capturing agent. COX activity was observed in the intracristal spaces and intermembrane spaces of trophoblastic mitochondria. The number of mitochondria posi tive for COX staining was decreased markedly in the placentae of the w omen with pre-eclampsia. Trophoblastic mitochondrial dysfunction may b e present in placenta of patients with pre-eclampsia. (C) 1997 W. B. S aunders Company Ltd.