Enzyme, nitrogen, and DNA concentrations in sarcoma 180 in mice treated with 6-mercaptopurine.

The concentrations of homogenate-nitrogen, of DNA, and the activities of various nucleotidases, adenosine deaminase, cathepsin and lactic dehydrogenase have been studied in homogenates of Sarcoma 180 from non treated mice, from mice given injec tions of 6-carboxymethylcellulose in saline, and from mice treated with 6-mercaptopurine suspended in saline containing 6-carboxymethylcellulose. Statistically significant increases in the activities of all the nucleotidases, adenosine deaminase, and cathepsin have been observed in tumor homogenates of mice treated with 6-mercaptopurine. Statistically significant decreases in tumor weight, homo genate-nitrogen, DNA, and lactic dehydrogenase have been observed in the same homogenates. The tumor homogenates of the controls receiving 6-carboxymethylcellulose in saline showed only increases in adenosine deaminase and cathepsin which, however, did not reach the activity levels attained in homogenates of mice treated with 6-mercapto purine. The significance of the findings is discussed.