猫の中腦および間脳における遠心線維の走行路と大さに関する研究

Globus pallidus, putamen and the adjacent part of internal capsule, head of caudate nucleus and lateral part of thalamus were surgically destroyed in cats, and degeneration of nerve fibres was seen in the internal capsule, cerebral peduncle, thalamus, espcially lamina medullaris externa, stratum reticulatum thalami, ansa lenticularis, pedunculus thalami inferior, corpus Luysi, Darkschewitsch' nucleus, Cajal' interstitial nucleus, radiatio tegmenti, brachium colliculi caudalis, Forel' and Meynert' decussation, bilateral red nuclei, tractus tegmenti medialis, fasciculus praedorsalis, substantia nigra, lemniscus medialis, stratum fibrosum pontis etc. Eleven parts were selected for investigation among these parts of degeneration, i.e. capsula interna (or pes pedunculus cerebri), lamina medullaris externa, pedunculus thalami inferior, stratum reticulatum thalami, rediatio tegmenti, nucleus ruber minocellularis, nucleus ruber magnocellularis, lemniscus medialis, brachium colliculi caudalis, substantia nigra, and stratum fibrosum pontis and the diameter of the nerve fibres of these selected parts was measured. Most of the fibres are thicker and the mean diameter of these parts are ranged in the following order from the thicker to the thinner: capsula interna (or pes pedunculus cerebri), nucleus ruber magenocellularis, lemniscus medialis, brachium colliculi caudalis, lamina medullaris externa, nucleus ruber minocellularis, stratum fibrosum pontis, pedunculus thalami inferior, radiatio tegmenti, stratum reticulatum thalami and substantia nigra. The extrapyramidal nerve fibres are mostly thinner than the pyramidal ones in these parts. When the thickness of the nerve fibre of the peripheral and spinal nerves reported in literature, the peripheral nerve fibres are the thickest and those in the brain are the thinnest and a marked difference between them is oberserved.