[Effect of ethanol on tone of isolated smooth muscle of the the pulmonary artery].

The response of the pulmonary artery smooth muscle tone to ethanol, and the effects of haloperidol (a dopaminergic receptor blocker), propranolol (a beta-adrenergic receptor blocker) and verapamil (a calcium channel blocker) on the response to ethanol were studied using the dog pulmonary artery smooth muscle. The results have shown that ethanol consistently induces a dose-dependent contraction of pulmonary artery smooth muscle which is not substantially modulated by the prior administration of haloperidol, but is partially blocked by propranolol, suggesting that catecholaminergic receptors are partly involved in the mediation of the ethanol induced pulmonary artery smooth muscle contraction. However, the results of this study have shown that ethanol induced contraction of pulmonary smooth muscle is not altered by verapamil in doses which blocked the contractil response of airway smooth muscle to ethanol. Due to these studies it can be concluded that ethanol, acting directly on pulmonary vasculature, might contribute to development of pulmonary hypertension and cor pulmonate chronicum.