シジミエキスの催リンパ作用機序,特に二次的活性物質の遊離について

A water-soluble, alcohol-insoluble extract was prepared from the viscera of Corbicula japonica Prime. This was found to have a marked lymphagogic action on the thoracic lymph of a dog, and also a special action on the liver circulation, as was found earlier by Yamasaki et al. (Folia pharmacol. japon. 31, 22, 1941) with the extract prepared in a similar manner from Corbicula sandai Reinhardt. The lymphagogic action and actions of elevating portal pressure and of lowering arterial pressure of this extract were all more marked in the case of intraportal injection than by systemic injection. There was a marked tachyphylaxis in all these actions. After intravenous injection of this extract, there was no increase of histamine equivalent in the blood and thoracic lymph sufficient to account for the foregoing lymphagogic action and there was no change in the histamine content of the liver, muscles and the skin. Intraportal injection of adenosine triphosphate also effected an increase of thoracic lymph flow, decrease of its coagulability, and changes in the portal and arterial blood pressure and respiration as in the case of intravenous injection of the corbicula extract. A substance (or substances) exhibiting the maximum absorption at 255-260 mμ was detected in the plasma from the hepatic venous blood immediately after intraportal injection of this extract. These observations suggest that the lymphagogic action of this extract is due to adenosine triphosphate or some related substance liberated from the liver.