BIOLOGICAL AND INDUCTION EFFECTS OF PHENOBARBITAL AND 3-METHYLCHOLANTHRENE IN MINK (MUSTELA-VISION)

  • 1 January 1983
    • journal article
    • research article
    • Vol. 11  (5) , 441-445
Abstract
Mink were injected (i.p.) daily with 20 mg/kg of 3-methylcholanthrene (MC) or 40 mg/kg of phenobarbital (PB) for 3 days and killed 48 h after the last injection. The duration of anesthetic action of PB increased after each injection. MC-treated mink became anorexic and lost substantial body weight. PB caused enlargement of liver and lungs; MC caused liver atrophy. No major treatment-related morphologic changes including amount of endoplasmic reticulum (ER) in liver were revealed by EM examination. Microsomal protein content was not increased and NADPH cytochrome P-450 reductase was not induced in liver by PB or MC. Cytochrome P-450 (448) was increased 3.2-fold by PB and 2.5-fold by MC. Cytochrome b5 was increased 2.3-fold by MC but was not affected by PB. Aminopyrine N-demethylase was enhanced 5.1-fold in activity by PB; hexobarbital hydroxylase was not induced. MC-treatment moderately increased the activities of benzo[a]pyrene hydroxylase (1.7-fold) and ethoxyresorufin O-deethylase (2.1-fold) but had no effect on ethoxycoumarin O-deethylase. The most distinctive features of the mink revealed by this study were lack of PB induction of the ER, microsomal protein content, NADPH-cytochrome P-450 reductase and hexobarbital hydroxylase, and lack of MC induction of cytochrome P-448-associated mixed function oxidases known to be highly responsive to MC in other species.