THE MECHANISM OF THE SEROTONIN RELEASING ACTION OF CONGO RED AND THE ROLE OF SEROTONIN IN COLLOID SHOCK

Abstract

Studies were carried out on the mechanism of action of congo red in releasing 5-HT [5-hydroxytrypt-amine] and on the role of 5-HT released in shock produced by colloids such as congo red, mastix and arsphenamine. It was suggested that a formation of precipitable complexes of fibrinogen with congo red induced agglutination or destruction of platelets and as a result platelet 5-HT was liberated into plasma. A parallel correlation was confirmed between shock-inducing activity of colloids and their 5-HT releasing activity. Congo red and mastix which presented the same type of shock syndrome in cats, produced a marked release of 5-HT from platelets in vitro. Inulin and gelatin, on the other hand, produced neither shock in cats nor release of 5-HT into plasma in vitro. The results obtained on arsphenamine were inconsistent because of technical difficulties. Polyvinylpyrrolidone, which completely inhibited the 5-HT releasing action of congo red, prevented the occurrence of shock induced by congo red completely. The above described facts and the results previously stated indicate that 5-HT plays an important role in shock induced by congo red. The mechanism of shock caused by colloids was discussed.