A GOLGI-STUDY OF HUMAN LOCUS-COERULEUS IN NORMAL BRAINS AND IN PARKINSONS-DISEASE

The locus coeruleus (LC) of eight adults without neurodegenerative dis ease and eight patients with Parkinson's disease was investigated by m eans of the Golgi-Braitenberg method for formalin-fixed human autopsy material. As with Golgi studies in the rat and cat, two main neuronal classes could be demonstrated in the human LC: (i) medium-sized fusifo rm and multipolar LC neurons known to contain neuromelanin and (ii) sm aller neurons of widely varying somatic shape and dendritic arborizati on which are considered to be intermingled neurons of adjacent brain s tem nuclei not containing neuromelanin. In Parkinson's disease, the Go lgi-impregnated medium-sized LC neurons were reduced in number. They s howed marked reduction of dendritic length, severe loss of spines, den dritic varicosities and swollen perikarya. The last two findings could be due in part to Lewy-body inclusions. The smaller non-noradrenergic neurons did not show severe pathological changes by the Golgi impregn ation technique, which is in line with the fact that only neuromelanin -containing LC neurons are affected in the pathological process of Par kinson's disease.