The heterogeneity of the nucleus raphes dorsalis in albino rats. A fluorescence histochemical and microelectrophoretic study.

In albino rats, the nucleus raphes dorsalis (NRD) of the midbrain was investigated using a sensitive fluorochroming procedure to detect indolamines in combination with a microelectrophoretic method to demonstrate the isoenzyme pattern of acetylcholinesterase (AChE). Based on the fluorescence histochemical appearance, 3 types of indolaminergic cells were identified in the various areas of the NRD. According to data of the literature and in agreement with our own results, the morphological heterogeneity of the NRD was shown. Significant differences of AChE specific zymograms of NRD regions (subgroups) demonstrate that organization of NRD is heterogeneously proved not only by morphological results but also in respect of enzyme constitution.