PT - JOURNAL ARTICLE AU - MARVIN A. PETERS AU - MARILYN TURNBOW AU - DORIS BUCHENAUER TI - THE DISTRIBUTION OF METHADONE IN THE NONPREGNANT, PREGNANT AND FETAL RAT AFTER ACUTE METHADONE TREATMENT DP - 1972 May 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 273--278 VI - 181 IP - 2 4099 - http://jpet.aspetjournals.org/content/181/2/273.short 4100 - http://jpet.aspetjournals.org/content/181/2/273.full SO - J Pharmacol Exp Ther1972 May 01; 181 AB - The 14C-labeled methadone administered to female rats was found to be distributed differently in the pregnant as compared with nonpregnant female control animals. The liver of the pregnant rat showed a 50% decrease in the concentration of methadone whereas a 3-fold increase in the concentration of methadone was found in the uterus. The concentrations in some of the other tissues studied varied to some extent; however, no significant differences were observed. The concentration of methadone in the fetal tissues was significantly lower than that found in the maternal tissues in all cases with the exception of the brain. The concentration of methadone in the brain of the fetus was 2 to 3 times the concentration present in the maternal brain. The three methods used in this study all gave similar values and comparisons with regard to the distribution of methadone in the nonpregnant, pregnant and fetal tissues. © 1972 by The Williams & Wilkins Co.