猫の知覚運動領野より中脳以上の皮質下諸核への投射について
スポンサーリンク
概要
- 論文の詳細を見る
This study has been carried out by the Nauta method with the special reference to the difference between projections from the coronary and sigmoid gyri. To compare in detail the projections from both coronary and sigmoid gyri to each other, in some of our cases the coronary gyrus in one side and the sigmoid gyrus in the other side were damaged respectively, since the amount of degenerating axons sometimes were different even in cases with similar lesions, probably due to the difference of staining conditions and survival period. The results obtained are summarized as follows. 1. Although Nauta emphasized peri-cellular nets of degenerating axons as the actual pattern of terminal degeneration in Nauta preparations, such a pattern of degenerating axons could be rather rarely observed in our cases. In this study the net of fine rosarylike degenerating axons (rows of fine and black dots of irregular shape) or the accumulation of very fine granular degenerating axons in gray substances were recognized as showing termination of fibers therein. The rosary-like degenerating axons in gray substances, which did not show net arrangement and were not accompanied with very fine granular degeneration, were supposed to terminate therein, unless they showed the pattern of passing over through the gray substances. 2. In our cases sections were prepared as far as the level superior to the decussation of the anterior commissure. 3. Projections from the sensory motor cortex to the subcortical nuclei superior to the mesencephalic level are generally ipsilateral. 4. The head of the caudate nucleus receives more numerous fibers from the coronary gyrus than the sigmoid as far as our cases are concerned. They enter the ventrolateral part of the head through the internal capsule isolatedly. 5. Projections from the coronary gyrus to the putamen are markedly recognized, while those from the sigmoid gyrus are few, if any, as far as our cases are concerned. Most of the fibers enter the putamen directly from the internal capsule, but partly via the external capsule or the 'external medullary lamella of the globus pallidus. Some of the fibers in the putamen, however, are fibers en passage which enter the amygdaloid nuclei. The gray substances connecting the putamen with the head of the caudate nucleus through the internal capsule also show degenerating axons. The more nearly they are situated to the putamen, the more densely can they be found. 6. Although projection fibers from the sensory motor cortex, especially from the coronary gyrus, travel downward through the fiber bundles found in the inferior part of the globus pallidus scattered and coursing longitudinally, if any few degenerating axons can be found in the gray substance of the globus pallidus apart from the most lateral part of this nucleus where small projections from the coronary gyrus can be seen entering via the lateral medullary lamella of the globus pallidus. 7. Fibers from both coronary and sigmoid gyri pass down through the fiber bundles found in the entopeduncular nucleus scattered and coursing longitudinally. Termination of fibers in the gray substance of the entopeduncular nucleus can not be definitely indicated. 8. Degenerating axons can not be found in the subthalamic nucleus apart from its inferior pole where rosary-like degenerating fibers enter from the cerebral peduncle. Most of them, however, seem to be fibers en passage to the regions situated dorsally. The degenerating fibers in Forel's tegmental field and zona incerta appear also to be mostly fibers en passage. Although there is some possibility that some of them terminate in the most inferior part of the subthalamic nucleus, Forel's tegmental field and zona incerta, the final decision will need further investigation. 9. Degenerating fibers in the fiber bundles found in the substantia nigra coursing longitudinally appear to be fibers en passage to the mesencephalic tegmentum and the branch of the cerebral peduncle which travels downward in this nucleus separately from the main group of the peduncle. In the superior end of the nigral nucleus rosary-like degenerating fibers can be seen entering through the cerebral peduncle and passing dorsally through the substantia nigra. Termination of fibers in the substantia nigra can not be definitely indicated in our cases. 10. Thalamus : more numerous fibers project to the reticular nucleus from the coronary gyrus than from the sigmoid; fibers in nearly equal number to the anterior ventral nuclens from both gyri; a little more numerous fibers to the lateral ventral nucleus from the coronary gyrus; the most marked projection, arising more numerously from the coronary gyrus, to the posterior ventral nucleus ; small but definite projection, arising from both gyri in nearly equal number, to the inferior part of the lateral central nucleus and nucleus centrum medianum. No termination of fibers can be remarkably indicated in the medial central nucleus, dorsal medial nucleus, dorsal lateral nucleus, pulvinar, medial and lateral geniculate bodies, and midline nuclei. 11. The coronary gyrus projects remarkably to the stratum lemnisci of the superior colliculus, the most dorsolateral part of the mesencephalic reticular formation and the lateral part of the mesencephalic central gray matter, projections to these regions from the sigmoid gyrus also can be seen, but distinctively less than from the coronary gyrus. Degenerating axons in the ventral part of the mesencphalic reticular formation arise in nearly equal number from both coronary and sigmoid gyri. 12. Both coronary and sigmoid gyri project to the magnocellular red nucleus. 13. Small but definite projections to the nuclei of Darkschewitsch and Bechterew from both sigmoid and coronary gyri. These nuclei compose the parvocellular red nucleus in cats with the interstitial nucleus of Cajal and Forel's tegmental field by the view of Ogawa.
- 千葉大学の論文
著者
関連論文
- 15. 放射性Diiodofluorescein(DIF)による脳腫瘍の部位診断(予報)(第337回千葉医学会例会(臨床))
- 6. Nauta法の吟味(第357回千葉医学会例会(基礎,臨床))
- 猫の知覚運動領野より中脳以上の皮質下諸核への投射について