Abstract
Cyclic nucleotide phosphodiesterase (PDE) was demonstrated by an immunocytochemical method on the electron microscopic level. The method was chosen was a preembedding PAP-technique with osmification of the diamino benzidine (DAB) reaction product. Antigenic sites of PDE were detected in synapses, on endoplasmic reticulum, microtubules, the nuclear envelope, the cytoplasma and processes of distinct neurons and glial cells. Only a little reaction product was found in the capillary endothelium. The morphology was better in comparison to enzymehistochemical methods. There was a good agreement between the localizations of the enzymatic reaction (16) and the antigenic sites of the PDE on the electron microscopic level.
