RELATIVE POTENCY OF NITROVASODILATORS ON HUMAN PLACENTAL VESSELS FROMNORMAL AND PREECLAMPTIC PREGNANCIES

The relative potency of glyceryl trinitrate (GTN), sodium nitroprussid e (SNP) and S-nitroso-N-acetylpenicillamine (SNAP) was determined in h uman placental arteries and veins from normotensive gestants and preec lamptic women. This study demonstrates that the potency of the three n itrovasodilators is similar in normal and preeclamptic pregnancies. GT N and SNP behave as strong vasodilators and were significantly more po tent as relaxant of venous than arterial segments. Meanwhile, SNAP was 1 order of magnitude less potent than GTN and SNP and is equally effe ctive in reducing induced tone in arterial or venous segments. These o bservations suggest that the placental vessels obtained from normotens ive and preeclamptic gestants resulted equally sensitive to the relaxa nt effect of each nitric oxide donor drug, and nitrovasodilators appea r to be an interesting option for further clinical research on the pre vention and management of preeclampsia.