A SIMPLE ENZYME-HISTOCHEMICAL METHOD FOR THE SIMULTANEOUS DEMONSTRATION OF ACETYLCHOLINESTERASE AND MONOAMINE-OXIDASE IN FIXED-FROZEN SECTIONS

We describe an enzyme histochemical technique for the simultaneous dem onstration of acetylcholinesterase (AChE) and monoamine oxidase (MAO) (Types A, B, or A+B) in fixed-frozen sections. Several regions in the mesencephalon and brainstem were examined for both somatic and neuropi l labeling. The results obtained are equivalent or superior to those o btained using previous methods for the individual localization of thes e enzymes. The simultaneous visualization of AChE and MAO in the same section allows the relationship of the two enzymes to be easily assess ed with brightfield microscopy.