Identification of in vivo liver metabolites of delta 6-tetrahydrocannabinol produced by the mouse

Abstract

Metabolites of delta 6-tetrahydrocannabinol (THC) were extracted from livers, separated from lipids by chromatography on Sephadex LH-20, and identified by combined gas chromatography and mass spectrometry. Three alcohols, delta 6-THD-7-oic acid, five diols, six triols, five monohydroxy acids, six dihydroxy acids, two substituted ketones, an epoxide, three diols produced by hydrolysis of the epoxide, three dihydro metabolites, and a glucuronide conjugate were identified. Several other metabolites were detected but not identified. The metabolites were similar to those produced by delta 1-THC in that allylic and side-chain hydroxylation coupled with carboxylic acid formation at C7 were the major biotransformation pathways. delta 6-THC was found to be metabolized more extensively via the epoxide-diol pathway than the delta 1-isomer.