[Responses of isolated hepatic artery segments to barium in the presence of a flavonoid (4-methylesculetin), indomethacin and acetylsalicylate].

The aim of this work is to study the mechanism by which 4-methylesculetin (4-Me) inhibits the Ba++ induced contraction in smooth muscle. The effect of 4-Me, alone or associated with ascorbic acid, on basal tone and Ba++ induced contraction of isolated hepatic artery strips have been studied. Experiments have been carried out in the presence of lysine acetylsalicylate (LAS) and indomethacin (IN), specific inhibitors of prostaglandin-synthetase. Both LAS and IN suppressed the depressive effect of 4-Me on the Ba++ dependent contraction. Therefore, it seems reasonable to conclude that the 4-Me influence could be mediated by prostaglandins release smooth muscle.