Abstract

Following the intravenous administration of 4 mg/kg of C¹⁴-labeled demethylchlortetracycline in two dogs, approximately 75% of the administered radioactivity was recovered in the urine and 15% in the feces by 7 days. Of the total excreted, approximately 93% was identified as unmetabolized demethylchlortetracycline. Methods used for identification of this compound were countercurrent distribution, paper chromatography and chemical derivation. Radio-activity determinations on serum taken at various hours following the dosage substantiated the property of prolonged maintenance of antibiotic in the blood stream following a given dose.

Following the intravenous dosage of 10 mg/kg of C¹⁴-labeled demethylchlortetracycline in two dogs, the distribution of radioactivity in the tissues of the animals was determined. The results indicated that, except for the fat, the antibiotic was distributed throughout the animal body.