%0 Journal Article %A JAMES F. CUMMING %A HAROLD W. McCLUNG %A GILBERT J. MANNERING %T THE EFFECT OF HEMORRHAGE ON THE RATE OF HEXOBARBITAL BIOTRANSFORMATION IN THE DOG %D 1971 %J Journal of Pharmacology and Experimental Therapeutics %P 595-601 %V 178 %N 3 %X The effect of hemorrhage on the rate of biotransformation of hexobarbital in the dog was studied. Increased amounts of blood loss progressively decreased the rate at which dogs biotransformed hexobarbital. The effect was measurable after blood loss of only 5 ml/kg. A single infusion of hexobarbital for four to six hours was found to have a significant inductive effect on the biotransformation of hexobarbital. When the hexobarbital infusion was reinforced by phenobarbital i.p. for five to eight days, further enzyme induction resulted. Rates of biotransformation of hexobarbital in induced animals after hemorrhage as high as 20 mg/kg exceeded rates observed in nonbled, noninduced animals. Hepatic cytochrome P-450 and hexobarbital (type I) binding to hepatic microsomal cytochrome P-450 increased markedly in induced dogs, but aniline binding (type II) decreased suggesting that induction caused a qualitative change in cytochrome P-450. © 1971 by The Williams & Wilkins Co. %U https://jpet.aspetjournals.org/content/jpet/178/3/595.full.pdf