The effects of ketamine HCl and barbiturate anaesthesia on the metabolic clearance and production rates of testosterone in the male rhesus monkey, Macaca mulatta.
The study compares metabolic clearance rates, production rates and serum levels of testosterone in conscious and ketamine and barbiturate anaesthetized adult male rhesus monkeys. Using the single injection technique for the determination of metabolic clearance rate, a significant increase in metabolic clearance rate from 430 +/- 71 l/day in conscious animals to 908 +/- 46 l/day for ketamine and 1224 +/- 174 1/day for barbiturate anesthetized animals was observed. Serum testosterone was increased from 106 +/- 9 ng/100 ml to 450 +/- 186 ng/100 ml in barbiturate anaesthetized animals, and this marked increase in serum testosterone was accompanied by a 13-fold increase in the production rate of testosterone from 0.44 +/- 0.04 mg/day to 6.0 +/0 3.3 mg/day. Serum testosterone levels and production rates were not significantly different in conscious and ketamine anaesthetized animals. Barbiturate anaesthesia caused continual changes in serum LH and testosterone levels over an observation period of 3.5 h. Serum LH gradually increased from 4.8 +/- 2.1 mIU/ml to 19.0 +/- 4.1 mIU/ml within 1 h, while serum testosterone rose from 214 +/- 63 ng/100 ml to 836 +/- 53 ng/100 ml within 2 h. In the light of these findings it may be concluded that barbiturate anaesthesia is not suitable for such prolonged studies of endocrine function. Effects exerted by ketamine anaesthesia are less pronounced.
D000818:Animals; D003243:Consciousness; D007649:Ketamine / Q000494:pharmacology*; D008251:Macaca / Q000378:metabolism*; D008253:Macaca mulatta / Q000378:metabolism*; D008297:Male; D008657:Metabolic Clearance Rate; D010424:Pentobarbital / Q000494:pharmacology*; D013739:Testosterone / Q000096:biosynthesis / Q000097:blood / Q000378:metabolism*
D013739:Testosterone; D007649:Ketamine; D010424:Pentobarbital