25-hydroxylation of vitamin D3 in rat liver: roles of mitochondrial and microsomal cytochrome P-450

Biochem Biophys Res Commun. 1987 Feb 13;142(3):999-1005. doi: 10.1016/0006-291x(87)91513-0.


A mitochondrial cytochrome P-450 fraction, which catalyzed 25-hydroxylation of vitamin D3 much more efficiently than intact mitochondria was isolated from livers of male and female rats. For comparison, a microsomal cytochrome P-450 fraction was isolated by the same procedures. The mitochondrial cytochrome P-450 from female rats catalyzed 25-hydroxylation as efficiently as the same material from male rats. The microsomal 25-hydroxylation was male specific. The 25-hydroxylase activity in intact mitochondria and the 25-hydroxyvitamin D3 concentration in serum were similar in male and female rats. There was no correlation between the 25-hydroxylase activity in microsomal cytochrome P-450 and the 25-hydroxyvitamin D3 concentration in serum.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcifediol / blood
  • Calcifediol / metabolism*
  • Cytochrome P-450 Enzyme System / metabolism*
  • Female
  • Hydroxylation
  • Male
  • Microsomes, Liver / enzymology*
  • Mitochondria, Liver / enzymology*
  • Rats
  • Rats, Inbred Strains
  • Sex Characteristics


  • Cytochrome P-450 Enzyme System
  • Calcifediol