モルモット胆のう条片の運動に対するadenosine 5'-triphosphateの作用と各種プリン受容体遮断剤の影響

Exogenously applied adenosine 5'-triphosphate (ATP) caused a biphasic response;a quick relaxation followed by a slow contraction . This response was not affected by atropine, phentolamine, propranolol and tetrodotoxin .Theophylline, quinidine and IBMX reduced ATP-induced contraction and had no effect on ATP-induced relaxation . On the other hand, apamin reduced ATP-induced relaxation and had no effect on ATP-induced contraction .Indomethacin remarkedly reduced ATP-induced contraction without affecting the relaxation.It was suggested that there were two types of receptors (apamin sensitive and apamin resistant) in the guinea-pig gallbladder .