Studies on the Change of Thioacetazone in vivo. VII

On the Change of Thioacetazone in the Liver; chiefly by Perfusion through Surviving Rabbit Liver

Abstract

Change of thioacetazone in the liver was examined by the perfusion method through surviving rabbit liver and it was found that thioacetazone is decomposed into p-acetylaminobenzaldehyde and thiosemicarbazide (Fig. 1), that the former is further oxidized to the acid, and that the latter is excreted through conjugation with glucuronic acid. The excretion of glucuronic acid during oral administration of thioacetazone was found to be clearly larger than that during normal times (Fig. 2), and the amount of glucuronic acid in the perfusion solution in the liver perfusion experiments was also larger when compared to the control (Fig. 3). Glucuronic acid thiosemicarbazone was detected by paper chromatography, p-Aminobenzaldehyde thiosemicarbazone was found to be well acetylated by rabbit liver (Fig. 4) so that the deacetylation product of thioacetazone in the gastrointestinal system is again acetylated in the body. It seemed that the detoxication of thioacetazone by conjugation with ethereal sulfuric acid does not generally take place.