Effect of passages of Morris hepatoma 5123D in F1 (Buffalo X Wistar) rats on permanent decrease of gamma-glutamyltranspeptidase activity

The Morris hepatoma 5123D after at least two passages in F1 (Buffalo X Wistar) rats shows quicker growth than the original tumor and bearers of it have much lower gamma-glutamyltranspeptidase activity in serum, urine, tumor and in some other organs. This new variant of the hepatoma was labeled as hepatoma 5123D/AS. Simultaneous implantation of hepatomas 5123D/AS and 5123D in the same rats prevents the increase of serum gamma-glutamyltranspeptidase activity. After surgical removal of the former tumor, the enzyme activity in serum quickly increases. No significant differences in some other peptidase activities were observed between the variant and hepatoma 5123D.