Related Experiment Video
Updated: Sep 26, 2026

A Plate-Based Assay for the Measurement of Endogenous Monoamine Release in Acute Brain Slices
Published on: August 11, 2021
Inhibition by Zn(2+) of A-form monoamine oxidase in monkey brain mitochondria
Toru Egashira1, Fusako Takayama, Kumiko Sakai
1Department of Pharmacology, Oita Medical University, Japan. egacy@oita-med.ac.jp
Abstract:
The effects of ZnSO(4) on mitochondrial monoamine oxidase (MAO) activity in monkey brain were compared with those in rat and rabbit, in vitro. After preincubation at 25 degrees C for 20 min with 1 microM ZnSO(4), MAO-A activity in monkey brain was about 50% using serotonin (5-HT) as a substrate, and the inhibition was proportional to the concentration of ZnSO(4). However, ZnSO(4) had no effect on MAO-B activity in monkey brain using beta-phenylethylamine (beta-PEA) as a substrate. The inhibition by ZnSO(4) of MAO-A activity was competitive and reversible. CdSO(4) also inhibits MAO-A, but not MAO-B in monkey brain mitochondria. ZnSO(4) did not inhibit either MAO-A or MAO-B activity in rat and rabbit brain mitochondria. These results indicate that the inhibiting action of Zn(2+) differs depending on animal species. In monkey brain mitochondria, MAO-A was highly sensitive to Zn(2+) and MAO-B was less sensitive. These results also suggest that Zn(2+) may regulate the level of catecholamine content in monkey brain.
Related Concept Videos
Enzyme Inhibition
Electron Transport Chain: Complex I and II
ROS generation is regulated and maintained at moderate levels necessary...
Indirect-Acting Cholinergic Agonists: Mechanism of Action
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex, leading to...
Preparation of Amines: Reductive Amination of Aldehydes and Ketones
