Fragmentation of the Golgi apparatus of Betz cells in patients with amyotrophic lateral sclerosis

The Golgi apparatus (GA) of the large pyramidal motor neurons in the cerebr al cortex (Betz cells), was examined in sixteen patients with sporadic amyo trophic lateral sclerosis (ALS), in one patient with familial ALS (FALS), a nd in ten non-ALS age matched controls including one patient with Huntingto n's disease and one patient with a brain infarct. The GA was immunostained with an antibody against the MG-160 protein, a conserved sialoglycoprotein of the medial cisternae of the organelle. In ALS, 13.2% of counted Betz cel ls had fragmented GA in contrast to 0.6% in the ten non-ALS controls. The f ragmentation of the GA of Betz cells was identical to that previously repor ted in spinal cord motor neurons from patients with sporadic ALS and in tra nsgenic mice expressing the G93A mutation of the gene encoding the Cu/Zn su peroxide dismutase. The striking morphological similarity between the fragm entation of the GA observed in Betz cells and in spinal cord motor neurons suggests that a similar pathogenic mechanism is responsible for both, and t hat the fragmentation of the GA of the spinal cord motor neurons is not a c onsequence of deafferentation due to the degeneration of the Betz cells. (C ) 1999 Elsevier Science B.V. All rights reserved.