Aminotriazole is a potent inhibitor of alpha-oxidation of 3-methyl-substituted fatty acids in rat liver.

The production of CO2 and formate in isolated rat hepatocytes incubated in the presence of 3-methyl[1-14C]margaric acid was investigated. Production rates of formate were approximately 4-fold lower than those of CO2. Aminotriazole (3-amino-1, 2, 4-triazole), an irreversible inhibitor of catalase, potently suppressed alpha-oxidation of 3-methylmargaric acid, whereas beta-oxidation of palmitate, 2-methylpalmitate and trihydroxycoprostanic acid and conversion of exogenously added formate to CO2 were not or only slightly affected. This shows that aminotriazole is not only an inhibitor of catalase, but also of alpha-oxidation of 3-methyl-substituted fatty acids.