Pentobarbital pharmacokinetics

Being one of the long-time standards in basic psychopharmacology, there are few major variants to the procedure apart from the kind of barbiturate employed. Several barbiturates undergo clear hepatic metabolism, for example pentobarbital and phenobarbital, thereby confounding interpretations because of pharmacokinetic and metabolic factors. Indeed, one modification of the method has been specifically employed to estimate enzyme induction in the liver as indicated by more rapid barbiturate metabolism. Animals given a pre-exposure to a test substance are then exposed to a standard dose of phenobarbital (80 mg/kg i.p.) 24 hours later and assessed for sleep duration. The presence or absence of a decrease in sleep duration is taken as an index of the hepatic enzyme induction produced by the test substance (Kushikata et al. 2003). 

C. E. Cook, T. B. Seltzman, C. R. Tallent, B. Lorenzo, and D. E. Drayer, Pharmacokinetics of pentobarbital enantiomers as determined by enantio-selective radioimmunoassay after administration of racemate to humans and rabbits, f. Pharmacol. Exp. Therap., 243 779-785 (1987). 

Sams, R.A. Muir, W.W. Detra, R.L. Robinson, E.P. Comparative pharmacokinetics and anesthetic effects of methohexital, pentobarbital, thiamylal, and thiopental in greyhound dogs and non-greyhound, mixed-breed dogs. Am. J. Vet. Res. 1985, 46, 1677-1683. 

Hatanaka T, Sato S, Endoh M, Katayama K, Kakemi M, and Koizumi T (1988) Effect of chlorpromazine on the pharmacokinetics and pharmacodynamics of pentobarbital in rats. Journal of Pharmacobiodynamics 11(1) 18-30. 

CE Cook, et al. Pharmacokinetics of pentobarbital enantiomers as determined by enantioselective radioimmunoassay after administration of racemate to humans and rabbits. J Pharmacol Exp Ther 241 779, 1987. 

Nguyen, K.T. Stephens, D.P. McLeish, M.J. Crankshaw, D.P. Morgan, D.J. Pharmacokinetics of thiopental and pentobarbital enantiomers after intravenous administration of racemic thiopental. Anesth. Analg. 19%, 83, 552-558. 

Microsomes prepared from patients treated with pentobarbital and/or phenobarbital are reported to have stimulated docetaxel metabolism strikingly whereas those prepared from a patient taking prednisone did not. In a study in patients with metastatic prostatic cancer, prednisone did not significantly affect the pharmacokinetics of docetaxel. ... 

Raskovic, A., O. Horvat, V. Jakovljevic, J. Sabo, and R. Vasic. 2007. Interaction of alcoholic extracts of hops with pentobarbital and diazepam in mice. Eur. f. Drug Metab. Pharmacokinet. 32(l) 45-49. 

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