Golgi and computer morphometric analysis of cortical dendrites in metabolic storage disease

Golgi and computer morphometric analysis of neuronal dendrites was done on four cases, one each of Tay-Sachs disease, infantile type 2 sialidosis, Hurler's syndrome, and Sanfilippo's syndrome. There were large meganeurites on pyramidal neurons in Tay-Sachs disease, and small ones in Hurler's and Sanfilippo's syndromes. All the meganeurites in these three diseases were predominantly distal to the soma in layer 3, but close to it in layer 5. These findings may be accounted for by different rates of ganglioside accumulation and cortical neuronal morphogenesis. Computer morphometric analysis revealed atrophic or less developed layer 5 dendritic length and branching in Tay-Sachs disease, sialidosis, and Hurler's syndrome compared with tissues from control patients. These dendritic changes may be secondary to ganglioside accumulation or due to abnormal surface membrane production during dendritic development. This study contributes to an understanding of how enzyme deficiency is translated into abnormal cell structure and, presumably, function.