The metabolism of ¹⁴C-cyclohexylamine in mice and two strains of rat

Abstract

1. After administration of ¹⁴C-cyclohexylamine (35–500 mg/kg) to male mice and rats, 80% of the dose of ¹⁴C was excreted in the urine, mostly within the first 24 h after dosing.

2. In Wistar rats, 7–9% of the ¹⁴C in the 0–24h urine was present as cis-4-aminocyclohexanol, with a similar amount as the corresponding 3-isomers. In the DA rat, only 1–2% of the ¹⁴C, and in mouse <1% of the ¹⁴C was present in the urine as aminocyclohexanols; unchanged cyclohexylamine accounted for about 95% of the activity.

3. The extent of metabolism was not affected by either dose or route of administration. The species differences in metabolism may be implicated in the differences in toxicity during chronic high-dose administration.