Amino-Acid Decarboxylase Activities in Rat Hepatoma

Abstract

The effects of pH, substrate concentration and addition of benzene on the rate of histamine production by extracts of rat hepatoma and guinea-pig kidney have been determined, and manometric studies of the DOPA and 5-HTP decarboxylase activities of these extracts have also been made. The histidine decarboxylases of the two tissues have quite different properties, and the histidine decarboxylase of the rat hepatoma is not associated with 5-HTP and DOPA decarboxylase activities. Whereas the urinary histamine output of hepatoma-bearing female August rats is greatly raised, the 5-HIAA output lies within the normal range.