Metabolism of bladder carcinogens. 3. The metabolic path of 2-[8−14C]naphthylamine in several animal species

Abstract

After the intraperitoneal injection of single doses of 2-[8-Cl4]naphthylamine into the dog, rabbit, guinea pig, rat and mouse (approximately 1 mg/kg body wt.) the dog excretes only about 3% of the radioactive material in the feces, the guinea pig, rabbit and mouse about 10-15% and the rat almost 30%. The amount in urine varied from 62 to 90%. The small amount excreted by the dog in the feces is accounted for by low excretion in the bile. Paper chromato-grams of urines show the differences in metabolism of 2-[8-Cl4] naphthylamine in these species. The concentrations of radioactivity in the bile and in the blood of a dog and of a cat, after intraperitoneal injection, vary in a similar manner. The concentration at a given time is very much higher in the bile than in the blood. Radioactivity is detectable in the blood of dogs and guinea pigs for several weeks after a single injection. In the dog the activity is shared between plasma and cells, but in the guinea pig after 3 weeks the activity is entirely in the cells. The persistent activity in the blood of rats, after a single injection, is entirely in the contents of the cells, not in the plasma (previously shown) or in the red-cell envelope. 2-[8-C14]Naphthylamine is rapidly absorbed through the skin of the rat and the dog, being readily recognizable in the blood within a short time after application to the skin. 2-[8-C14]Naphthylamine is absorbed from the bladder into the blood of a cat to a notable extent, but 2-amino-l-[8-Cl4]naphthyl'' hydrogen sulphate is absorbed very much less readily.