[Contraction of the isolated stomach of the rat as a result of stimulation of postganglionic fibers in the presence of 4-methylesculetol].

Abstract

It is known that the bioflavonoids as the Ca++ have an enhancing effect on the transmitter release in different cholinergic nerve-endings. For this reason, it is seemed interesting to study the influence of the separately tested 4-methylesculetin or associated with the ascorbic acid and comparatively the Ca++ concentration increase on the isolated rat stomach response by electrical transmural stimulation achieved in presence or absence of hexamethonium. Both the 4-methylesculetin and the ascorbic acid have always increased the response of the preparation submitted to electrical transmural stimulation. The 4-methylesculetin effect resulted particularly strong if the substance was employed with the ascorbic acid. The enhancing effect of the 4-methylesculetin, obtained with or without the ascorbic acid, is resulted comparatively lesser in presence of hexamethonium. On the basis of the evident analogy between the 4-methylesculetin effects and the ones determined by the increased Ca++ concentration, it can be supposed that the bioflavonoid facilitates the transmitter release in the pre- and postganglionic nerve-endings. The results here reported, confirm other previous observations accomplished on different cholinergic nerve-endings and could substain the hypothesis according to which the 4-methylesculetin increase the Ca++ transport through the biological membranes.