Metabolic Alterations of Catechoiamines and Other Compounds In Elasmobranch Tissues

Abstract
All tissues of a variety of sharks studied contained catechol-O-methyl transferase (COMT). The most active tissues were inter-renal, kidney and liver. Monoamine oxidase activity was also demonstrated. N-methyl transferases were shown to be present but very low in activity. COMT was found to be a particulate enzyme, associated with the microsomal fractions. O-demethylation was observed in some shark species and shark liver showed weak azo-reductase activity. Nitro-reductase activity was not found.