Quantitative aspects on mitochondrial monoamine oxidase in human platelets.

The number of monoamine oxidase molecules in human blood platelets has been estimated by titrating them with the irreversible monoamine oxidase inhibitor pargyline to be about 900 per thrombocyte and 200--300 per thrombocyte mitochondrion. It has also been calculated that monamine oxidase constitutes about 1/5,000 of the platelet mitochondrial outer membrane surface. Molecular turnover numbers for benzylamine and tyramine have been estimated to be about 1,470 and 720, respectively.