DISTRIBUTION OF TYPE-A AND TYPE-B MONO-AMINE OXIDASE ACTIVITIES IN RAT AND CHICKEN SKELETAL-MUSCLE AND NERVES

The monoamine oxidase (MAO) activities and proportions of type A and type B MAO in rat and chicken skeletal muscles, sciatic nerves, phrenic nerves, brachial plexi, spinal cords and motor cortices were studied. Skeletal muscle contained mainly or exclusively type A MAO. The MAO in neural tissue of both species was 30-95 per cent type A, with chicken neural tissue tending to have more type B MAO than the rat. There was no evidence of a correlation between the total MAO activity of particular nerves and the MAO activity of the skeletal muscles they innervate. The MAO activity of the skeletal muscles did not correlate with their frequencies of contraction. © 1979.