[Effect of a flavinoid (4-methylesculetin) on the response of isolated calf coronary arteries to histamine in the presence of indomethacin].

: The aim of this work is to study the mechanism by which 4-methylesculetin (4-Me) cause the relaxation or inhibit the histamine induced contraction in the smooth muscle. The effect of 4-Me, alone or associated with ascorbic-acid, on basal tone and histamine induced contraction of isolated coronary strips have been studied. Experiments have been carried out in the presence of indomethacin (IN), specific inhibitor of prostaglandin synthetase. IN-decreased, but did not abolished, the 4-Me induced relaxation and reduced or suppressed the depressive effect of 4-Me on the histamine dependent contraction. Therefore, it seems reasonable to conclude that the 4-Me influence could be mediated by prostaglandins release in the smooth muscle.