Studies were made about enzymatic activities both in serum and hepatic tissue of patients with liver disease and of animals with experimental liver injury. The enzymes.determined were glutamic oxalacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), glucose-6-phosphatase (G6Pase), aldolase (Ald.), alkaline phosphatase (Alk. ph.) and arginase (Arg.).
The results obtained were summarized as follows:
1) When enzymatic activities were determined on biopsied hepatic tissue, in which only few mg. of wet weight could be obtained, the ultra-micro method was devised and employed. There was no difference between the enzymatic activities measured by the ultra-micro method and these by macro method.
2) All of serum enzymatic activities of patients with liver disease showed a tendency of increasing. In patients with hepatic parenchymal damage, the enzymatic activities, especially GOT and GPT, elevated remarkably. In patients with liver cirrhosis, serum GPT activities remained slightly elevated. Serum G6P ase activities increased much often in almost all kind of liver disease.
3) Liver enzymatic activities had a tendency of increasing. In patients with hepatitis and obstructive jaundice, GPT and G6P ase activities in some cases decreased distinctly. In patients with liver cirrhosis, GPT activities also decreased. The activities of Alk. ph. tended to increase, especially in patients with obstructive jaundice and liver cirrhosis.
4) In dogs injured by carbon tetrachloride, it was observed that increased serum enzymatic activities corresponded to decreased hepatic enzymatic activities. Therefore it was interpreted that the elevation of serum enzymatic activities resulted from releasing of enzymes from damaged liver cells into blood stream. Serum GOT and GPT activities changed most closely related to liver histological findings. Other serum enzymes except GOT and GPT showed delayed normalization of increased activities. Serum G6P ase activities elevated remarkably already 6 hours after carbon tetrachloride administration. Alk. ph. activities alone increased slowly both in serum and liver, so that it was assumed that disorder in excreting function of liver resulted in elevating of serum Alk. ph. activities.
5) GPT activity of cirrhotic liver of rats, experimentally induced by feeding the diet containing Penicillium Islandicum Sopp, decreased distinctly. However GOT activity in the same rat liver did show slight decrease. These facts indicated that the reduction of enzyme production of GPT occured in liver cells, and would explain the not so high increase of serum GPT activity in these rat.
It was concluded in these studies that determination of serum enzymatic activities, especially GOT and GPT, had great clinical significance in diagnosis and prognosis of liver disease, especially of hepatic parenchymal disorder.