@article {1731,
	title = {Disposition of (15,16-3H)naltrexone in the central nervous system of the rat.},
	journal = {Drug Metab Dispos},
	volume = {4},
	year = {1976},
	month = {1976 May-Jun},
	pages = {276-80},
	abstract = {<p>After injection of (15,16-3H)naltrexone (10 mg/kg s.c.) in male Wistar rats, peak concentrations of drug occurred in brain and plasma within 0.5 hr. Levels of naltrexone were sustained in brain between 2 and 24 hr and were barely detectable at 48 hr. Significant amounts of metabolities were present in brain and plasma at longer time periods. The t1/2 of naltrexone in brain and plasma were approximately 8.0 and 11.4 hr. respectively. The brain/plasma ratios of naltrexone at earlier times (0.5-1 hr) were higher than those at later times. The binding of naltrexone in vitro with rat plasma proteins in concentrations of 1-10 mug/ml ranged between 41 and 59\% 6beta-Naltrexol was present in very small amounts in brain but not in plasma. In addition to 7,8-dihydro-14-hydroxynormophinone and 7,8-dihydro-14-hydroxynormophine, tentative evidence was obtained for three other metabolites of naltrexone in brain. These metabolites were also present in plasma in addition to free and conjugated naltrexone and its N-dealkylated metabolites.</p>},
	keywords = {Animals, Blood-Brain Barrier, Brain, Chromatography, Thin Layer, Male, Naloxone, Naltrexone, Rats},
	issn = {0090-9556},
	author = {Misra, A L and Bloch, R and Vardy, J and Mul{\'e}, S J and Verebely, K}
}
