Experimental and Clinical Studies on Serum γ-Glutamyl Transpeptidase Activity

Abstract

Purpose; The present were conducted to clarify the clinical singnificance of serumγ-glutamyl tranpeptidase activity.
Method; Estimation of serum r-glutamyl transpeptidase activity was made by followingthe original method of Szewczuk and Orlowski. In this work a-(-N-γ-DL-glutamyl)-aminopropionitrile was used as the substrate.
Results; A) Clinical experiments. 1) While an elevation of serum γ-gluamyl transpeptideseactivity was seen in a slight or moderate degree in acute and chronic, portalcirrhosis and cardiac cirrhosis. In acute hepatitis while serum γ-glutamyl transpeptideseshowed relation with transaminase activity. 2) A remarkable elevation of serum γ-glutamyltranspeptidase activity appeared in the presence of obstructive jaundice and biliarycirrhosis. In this case while serum γ-glutamyl transpeptidase activity showed aclose to parallel ralation wihe that of alkaline phosphatase activity and leucine amino-peptidase activity, there was no correlation with serum transaminase acivity and liverfunction tests. 3) High serum γ-glutamyl transpeptidase activity was seen in primaryor metastatic liver cancer. On the contrary, since.alkaline phosphatase activity andleucine aminopeptidase activity was merely seen at time showing a slight or moderatedegree of activity, it follows that no correlation was seen between the two. 4) So faras examined, in various afflictions other than those of the liver and biliary duct, noremarkable in the γ-glutamyl transpeptidase activity was seen.
B) Animal experiments. A slight elevation of serum γ-glutamyl transpeptidase activitywas seen in dogs with acute or chronic liver injury induced by CCl4, and in dogswith ureteral ligation or with acute pancreas damage by autobile infusion. On the contrary, a remarkable elevation of serum r-glutamyl transpeptidase activity was seen indogs with liver cancer induced by dimethylaminoazobenzene. In addition the degree of γ-glutamyl transpeptidase activity was compared with serum transpepti- dase activitywas compared with serume transaminase activity, alkaline phosphatase activity andleucine aminopeptidase activity.
Conclusion; Since a remarkable elevation of serum γ-glutamyl transpeptidase activitywas seen in the presence of obstructive jaundice and liver cancer, it is our belief thatour present findings may contribute to the diagnosis of the above mentioned afflictions.