title: Characteristics of monoamine oxidase activity in brain and other organs of the adult bullfrog, Rana catesbeiana.
abstract: 1. Monoamine oxidase (MAO) activity was measured in brain, liver, kidney and intestine of the adult bullfrog by a fluorometric method. 2. All tissues contained both type A and type B MAO, on the basis of responses to specific inhibitors, but with different ratios in each tissue. 3. MAO activity was optimum at 30 degrees C. However, MAO type B showed greater activity changes related to incubation temperature than did type A. 4. The Michaelis constant (Km) of MAO also varied with temperature, with a nadir around 20 degrees C. The functional significance of this is not clear. 5. Arrhenius plots showed that the activation energy for MAO B was higher than for MAO A.
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology*; D005260:Female; D007422:Intestines / Q000201:enzymology; D007668:Kidney / Q000201:enzymology; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism*; D011892:Rana catesbeiana / Q000378:metabolism*; D013696:Temperature
chemical_list: D008995:Monoamine Oxidase