Urinary excretion of 6-keto-PGF1 alpha TxB2 and PGE2 in a rat animal model for preeclampsia-like syndrome.

The etiology of pregnancy induced hypertension (PIH) is still unknown. The pathophysiology must be clarified. In this paper we present an animal model where hypertension in pregnant and non-pregnant rats was induced by an experimental reduction of uteroplacental blood flow. Thus, a preeclampsia-like syndrome could be studied under defined conditions. The eicosanoid system was investigated for pathophysiological alterations of the kidney by measuring urinary excretion of 6-keto-PGF1 alpha, TxB2 and PGE2 with radioimmunoassay at day 18 of pregnancy. First, in gravid control animals concentrations of all three prostaglandins were significantly elevated compared to non-gravid controls. However, in hypertensive gravid rats urinary concentrations of these prostaglandins fell even below the levels of non-gravid controls. The observed decrease was more pronounced for the vasodilatory 6-keto-PGF1 alpha and PGE2 than for the vasoconstrictive TxB2. Our results demonstrate that an experimental reduction of uteroplacental blood flow in the rat culminates in symptoms which clinically (hypertension, proteinuria) and pathophysiologically (eicosanoid system) resemble to preeclampsia.