Distribution of Kinase and Deaminase of 1-β-d-Arabinofuranosylcytosine in Tissues of Man and Mouse

摘要: Summary 1-β-d-Arabinofuranosylcytosine (ara-C), an important antitumor agent, must be converted to the nucleotide by deoxycytidine kinase (K) in order biologically active. It is inactivated ara-C deaminase (D) 1-β-d-arabinofuranosyluracil. The enzymes are widely distributed normal and neoplastic tissues of both man mouse. Low K high D activities, thus low ratios D, were demonstrated chronic myelogenous leukemic cells human peripheral white marrow. Acute lymphocytic either from peripherals or marrows had relatively K/D ratios. A was spleens spleen liver whereas mouse kidney D. On basis equal body weight, contained more than did tissues. This corresponds well with faster catabolic rate vivo. In mice, i.p. administration a inhibitor, tetrahydrouridine (100 mg/kg), decreased amount 1-β-d-arabinofuranosyluracil proportionally increased excreted urine. view higher mouse, combination may value clinically alone.