摘要：A mouse hepatic microsomal enzyme that catalyzes the oxidation of cannabinol (CBN) to 11-hydroxycannabinol (11-OH-CBN) was characterized. 11-OH-CBN formed was determined by HPLC. The reaction required NADPH as a cofactor and the optimal pH for the reaction was at 7.8. The Km and Vmax values for the reaction were 122 μM and 8.82 nmol/min/mg protein, respectively. The reaction was inhibited by inhibitors of cytochrome P450 such as SKF 525-A and by cannabidiol. The pretreatment of mice with phenobarbital significantly increased the enzyme activity but not with 3-methylcholanthrene, whereas that with cobaltous chloride significantly decreased the activity. These results indicate that cytochrome P450 plays a major role in the formation of 11-OH-CBN in the mouse hepatic microsomes.
