PT - JOURNAL ARTICLE AU - Zauder, Howard L. TI - THE EFFECT OF PROLONGED MORPHINE ADMINISTRATION ON THE <em>IN VIVO</em> AND <em>IN VITRO</em> CONJUGATION OF MORPHINE BY RATS DP - 1952 Jan 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 11--19 VI - 104 IP - 1 4099 - http://jpet.aspetjournals.org/content/104/1/11.short 4100 - http://jpet.aspetjournals.org/content/104/1/11.full SO - J Pharmacol Exp Ther1952 Jan 01; 104 AB - 1. Adrenal cortical hormones or compounds which cause their release bring about an increase in the total TBA values and lipid content of rat livers. 2. The increase in liver lipid does not interfere with detoxification of morphine in vivo. 3. Rats excrete the greatest part of an administered dose of morphine in the conjugated form. As tolerance to the drug develops the amount of morphine appearing in the urine decreases. This decrease is at the expense of the conjugated rather than of the free fraction which remains constant. 4. Liver slices taken from morphine-tolerant rats or from rats that have received adrenal cortical extract for a prolonged period conjugate more morphine in vitro than do slices of normal livers. The possible mechanisms of this increased ability to conjugate morphine are discussed.