Studies on the metabolism of testosterone trans-4-n-butylcyclohexanoic acid in the cynomolgus monkey, Macaca fascicularis.
Metabolism of intravenously administered testosterone trans-4-n-butylcyclohexanoate (T bucyclate), a potent, long-acting androgen, was studied in cynomolgus monkeys (Macaca fascicularis). About 5% of the radioactivity of a dose of doubly labeled ester (14C, 3H) was excreted via the gastrointestinal tract. Most of the administered radioactivity was excreted in the urine within 120 h. No intact T bucyclate was recovered from either compartment. Tritium attributed to bucyclic acid and its metabolites was excreted rapidly (peak excretion was at 6h after injection), while 14C excretion, attributed to testosterone and its metabolites, extended over 4 days. Testosterone metabolites were excreted predominantly as sulfate esters. Analysis of urinary products derived from the bucyclic acid moiety of T bucyclate showed no products susceptible to glucuronidase treatment, and showed a mixture of unidentified solvolyzable and unconjugated products. No unmetabolized trans-4-n-butylcyclohexanoic acid was detected in urine or feces. It is concluded that metabolism of testosterone bucyclate is initiated in vivo in cynomolgus monkeys by hydrolysis of ester to testosterone and bucyclic acid. The bucyclate side chain is rapidly cleared, and the testosterone is retained in the circulation.
Monder
C
C
Population Council, NY 10021.
Marshall
D E
DE
Laughlin
L S
LS
Blye
R P
RP
D000818:Animals; D005243:Feces / Q000737:chemistry; D008099:Liver / Q000378:metabolism; D008252:Macaca fascicularis; D008297:Male; D013739:Testosterone / Q000031:analogs & derivatives* / Q000378:metabolism / Q000652:urine
C050320:testosterone 4-n-butylcyclohexylcarboxylic acid; D013739:Testosterone