Altered prostaglandin metabolism as a cause of pre-eclampsia: an implication on therapy

ABSTRACT

In a trial to declare the possible role of altered prostaglandin metabolism in the pathogenesis of pre-eclampsia, the plasma levels of 2 major antagonistic compounds have been estimated using enzyme immunoassay method; namely thromboxane A2 and prostacyclin, along with estimations of platelet count and ADP induced platelet aggregation. The study comprised 10 normal pregnant and 10 pre eclamptic females of comparable parity and gestational periods, as well as 10 normal age matched non-pregnant females for comparision. Mean platelet count was significantly lower in pre-eclamptic cases as compared to both normal pregnant and control groups, with no significant difference between the later 2 groups. Mean platelet aggregation percent was only significantly higher in normal pregnant females as compared to both pre-eclamptic and non-pregnant controls, using either low or usual doses of ADP. A significantly higher mean plasma thromboxane-B2 and a significantly lower mean plasma prostacyclin levels were observed in both normal pregnant and pre-eclamptic groups as compared to controls, with no significant difference in the level of either compound between the former 2 groups. A significant positive correlation between TXB2 level and each of systolic and diabolic blood pressures was observed in pre-eclamptic patients. A significant positive correlation was similarly observed between TXB2 level and ADP induced aggregation percent using both low and usual doses, only in non-pergnant controls. Moreover the levels of both TXB2 and PCI2 showed a direct significant correlation in both pregnant groups. The ratio of thromboxane B2/prostacyclin was however, significantly highrt in both pregnant groups as compared to controls as well as in pre-eclamptic patients as compared to normal pregnant females. A disturbed prostaglandin metabolism, with unchecked thrombogenic effect of thromboxane A2 was suggested as a potential mechanism for pre-eclampsia. The therapeutic use of low dose asprin as a selective cyclo-oxygenase inhibitor might be of help in prevention of the microcirculatory complications observed in this condition