Involvement of CYP2C in the metabolism of cannabinoids by human hepatic microsomes from an old woman

Biol Pharm Bull. 1995 Aug;18(8):1138-41. doi: 10.1248/bpb.18.1138.


The hepatic microsomal metabolism of cannabinoids was studied using the liver from an old woman. delta 8-Tetrahydrocannabinol, delta 9-tetrahydrocannabinol and cannabinol were biotransformed to their respective 11-hydroxy metabolites by a microsomal fraction with specific activities (pmol/min/mg protein) of 29.1, 47.1 and 27.9, respectively. In addition, both 11-oxo-delta 8-tetrahydrocannabinol and 11-oxo-delta 9-tetrahydrocannabinol were metabolized to the corresponding carboxylic acids with the microsomes. An antibody against mouse CYP2C29 almost completely inhibited 11-hydroxylation of the cannabinoids and microsomal aldehyde oxygenase (MALDO) activity for 11-oxo-delta 8-tetrahydrocannabinol and 11-oxo-delta 9-tetrahydrocannabinol, used as substrates, whereas an antibody against rat CYP3A2 conversely stimulated the 11-hydroxylation of delta 8-tetrahydrocannabinol and MALDO activity for 11-oxo-delta 8-tetrahydrocannabinol. The results indicate that a member of CYP2C is primarily responsible for the metabolism of the above cannabinoids in the human hepatic microsomes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Animals
  • Aryl Hydrocarbon Hydroxylases*
  • Cannabinoids / metabolism*
  • Cytochrome P-450 CYP3A
  • Cytochrome P-450 Enzyme System / metabolism*
  • Female
  • Humans
  • Hydroxylation
  • Membrane Proteins
  • Mice
  • Microsomes, Liver / enzymology*
  • Rats
  • Steroid 16-alpha-Hydroxylase*
  • Steroid Hydroxylases / metabolism*


  • Cannabinoids
  • Membrane Proteins
  • Cytochrome P-450 Enzyme System
  • Steroid Hydroxylases
  • Aryl Hydrocarbon Hydroxylases
  • Cyp3a2 protein, rat
  • Cytochrome P-450 CYP3A
  • Steroid 16-alpha-Hydroxylase