EFFECT OF ETHANOL ON HUMAN PLACENTAL TRANSPORT AND METABOLISM OF ADENOSINE

It has been suggested that adenosine is involved in the acute effects of ethanol in a number of tissues. The present study was undertaken to evaluate the role of adenosine on the vascular responses of perfused isolated human placental cotyledons after the acute administration of ethanol. The possibility that ethanol may effect the uptake and metabo lism adenosine was also investigated. Uptake of adenosine was studied using the single-circulation paired-tracer dilution technique. Both ad enosine and ethanol caused a dose-related increase in perfusion pressu re of placental lobules. Pharmacologically relevant concentrations of ethanol (10-65 mM) significantly inhibited the uptake of [H-3]adenosin e between 25 and 50 per cent. Thin-layer chromatographic analysis of t he perfusate after the administration of ethanol showed in a 17.9 +/- 0.6 per cent reduction of [3H]adenosine metabolism. These findings sup port the working hypothesis that placental adenosine, at least partial ly, mediates the placental disturbance elicited by the administration of acute ethanol, which may contribute to the pathogenesis of fetal al cohol syndrome. (C) 1997 W. B. Saunders Company Ltd.