Junzo Torii

Electron microscopic and enzyme histochemical studies of cerebellum, ocular and skeletal muscles in chronic progressive ophthalmoplegia with cerebellar ataxia

SummaryElectron microscopic and enzyme histochemical studies were performed on the cerebellum and the ocular and deltoid muscles from a 38 year old woman who developed bilateral ptosis at the age of nine years. Histologically the cerebellum appeared normal. The biopsies of three ocular muscles showed varying sizes of muscle fibers which were rounded and contained increased numbers of subsarcolemmal nuclei. The deltoid muscle stained by hematoxylin and eosin appeared normal, but the trichrome stain showed increased numbers of red granules within the sarcolemma corresponding ultrastructurally to increased numbers of abnormal mitochondria. These abnormal mitochondria displayed increased reaction products with LDH, NADH and SDH preparations, while the muscle gave normal reaction in phosphorylase, PAS and myosin ATP preparations. Chemical studies on the cerebellum showed normal proteolipids, glycolipids and phospholipids. Ultrastructurally, the cerebellum, the myofibers of three ocular muscles and the deltoid muscle exhibited abnormal mitochondria which showed peculiarly arranged circular cristae. They frequently contained paracrystalline structures which consisted of individual tubules arranged in a helical pattern. Frequently, the abnormal mitochondria were replaced by dense rectangular inclusions and occasionally showed complete transition to crystalline structures.

Electron miscroscopic and enzyme histochemical studies of the cerebellum in spongy degeneration

SummaryElectron microscopic and enzyme histochemical studies were performed on the cerebellum from a 9 month old Jewish boy with spongy degeneration. Histologically, the main pathological changes were noted in the Purkinje cell layer, the deeper areas of the granular cell layers and the subcortical white matter. Ultrastructurally, multiple vacuoles were present within the swollen cytoplasm and processes of protoplasmic astrocytes in the cortex, while in the subcortical white matter vacuoles were observed within splitting myelin lamellae as well as within astrocytes. There were also abnormal mitochondria within swollen protoplasmic astrocytic cytoplasm and processes which in ATPase preparations showed little or no reaction product. However, the fibrillary astrocytes were not swollen and contained intact mitochondria which showed normal reaction product in ATPase preparations. Since the myelin changes are known to be nonspecific and secondary to abnormal fluid accumulation, the characteristic distribution of the multiple vacuoles in the central nervous system in this disorder seems primarily to be related to swelling of the protoplasmic astrocytes.

Alterations of astrocytic organelles in various lipidoses and allied diseases

SummaryThe astrocytic organelles in 12 patients with various lipidoses and allied diseases were studied. Histochemically and ultrastructurally, astrocytes contained cytoplasmic inclusions which were identical to those seen in neurons from cases of similar disorders. In the early stage of these disorders, the astrocytic cytoplasm displays a close relationship between increased numbers of mitochondria and dilated smooth portion of the endoplasmic reticulum. In the more advanced stage, the mitochondria decrease in number, and the lipid bodies show close proximity to or continuity with the smooth portion of the endoplasmic reticulum. During the late stages of the disorder, the intracytoplasmic inclusion bodies become numerous, and the mitochondria are further reduced in number. It, therefore, appears that in astrocytes in these disorders the mitochondria and the smooth portion of the endoplasmic reticulum play an important role during the evolution of the intracytoplasmic lipid bodies. On the basis of these observations, the possible morphogenesis of lipid cytosomes is discussed.

Early central nervous system lesions in experimental hypercholesterolemia in normal and subdiabetic rabbits

SummaryBiochemical and morphologic studies were carried out on the early effect of hypercholesterolemia on the central nervous system in both metabolically normal and subdiabetic rabbits. Major biochemical difference was the elevation of non-esterified cholesterol in the subdiabetic animals. Histologically, Alzheimer type II astrocytosis was noted in the basal ganglia of the subdiabetic rabbits during the 4th week. The astrocytosis extended into the entire protion of the cerebrum and cerebellum during 2 to 4 months. In the metabolically normal rabbits on the cholesterol diet, on the other hand, similar astrocytic changes were noted after 2 months. Despite the fact that cholesterol crystals had frequently been noted in the capillary walls of the viscera after the 2nd week, similar changes were not observed in the blood vessels of the brains of both the subdiabetic and the metabolically normal rabbits during the 4 months of cholesterol feeding. These observations suggest that cholesterol deposits in the vascular walls are determined by the different rates of lipid metabolism in each individual organ.

Fine Structure of Early Tay-Sachs Disease

Tay-Sachs disease is an inborn error of glycolipid. It is characterized by massive accumulation of GM2-ganglioside (4), mainly in the brain and by the absence of the enzyme hexosaminidase A (5). Despite the significant increase of our knowledge of the biochemical aspects of this disorder during the past few years, the ultrastructural alterations of the neuronal organelles related to the accumulation and the evolution of the intracytoplasmic deposited lipid material at the early stage of Tay-Sachs disease are unknown.