The study investigates how the monoamine oxidase inhibitor tranylcypromine (TCP) affects various copper-containing amine oxidases from mammals, plants, bacteria, and fungi.
Only bovine plasma amine oxidase (BPAO), equine plasma amine oxidase (EPAO), and Arthrobacter globiformis amine oxidase (AGAO) showed significant activity loss when exposed to TCP, with BPAO's inhibition being fully reversible.
The findings suggest that TCP does not inhibit human kidney diamine oxidase (HKAO), indicating that HKAO inhibition is unlikely to contribute to the side effects of TCP in patients.