[Pharmacokinetics of 35S-tomizin in mice with leukemia L-1210]

A comparative study of the distribution of 35S-tomisin in the organism of intact (without neoplasia) mice and those with L-1210 leucosis was carried out. In both animal groups the tagged drug was found to be largely accumulating early after its introduction in the tissues of the liver, kidneys, intestines, spleen and lymph nodes. In 30 minutes time following introduction of 35-S-tomison 7.3 +/- 0.7 per cent of its amount was detected in the ascitic fluid. On centrifugation of the tagged drug its bulk (92-95 per cent) remained in the supernatant fluid. During the first 24 hours the drug leaves the body: 25-35 per cent with urine, 3-5 per cent--with feces and 0.1-0.3 per cent--with bile. In the urine of mice with leucosis the products of the 35S-tomisin biotransformation appear earlier than in intact animals. The most marked immunodepressive effect of tomisin was marked with its administration 24 and 48 hours after immunization.