• 作者： 謝正勇；鄭聰明；陳文彬；?振源
• 作者服務機構： 國立臺灣大學醫學院解剖學科
• 中文摘要： 利用36隻不計性別的成熟白鼠，進行其網狀脊髓徑系變性實驗，以Nauta氏?銀法染出陷於病理變性之該徑纖維軸索，以研究該徑系之起源、徑路、向尾側之延伸度、主要分佈之脊髓分節及其終末部在灰質中的分佈層次。所得結果如下： 白鼠網狀脊髓纖維之起源，可能在下位腦幹內側2/8（大多數）及外側1/3(少數）之網狀結構包括：橋腦網狀尾端核、網狀巨大細胞核，網狀腹側核及網狀微小細胞核。 橋腦網狀脊髓纖維經腦幹至脊髓，下行於兩側之脊髓腹側索，且可追?至第二薦髓節之高度。同側性纖維較異側者?多。此等變性纖維之終末部則分佈於同側之脊髓灰質第VII及VIII兩層中。但於第IX層仍可見少數變性纖維分佈於此。 延髓網狀脊髓纖維亦經腦幹至脊髓，下行於兩側之脊髓腹側索及外側索中，且可追?至第二薦髓節之高度。同側性之纖 維亦較異側者?多。此等纖經之終末部則分佈於兩側之脊髓灰質第VII及VIII兩層中。且具有軸體性及軸索樹突性突觸(axosomatic and axodendritic synaptic connection)。同側性者較異側性者?多。於第IX層中與其中之運動神經元具有 直接聯絡。於此橋腦毀傷者亦有同樣之現象。 網狀脊髓徑系可能具有某種程度的體區位排列現象。同時該徑系上接皮質網狀徑系，可能?溝通上位及下位運動神經元 間之橋樑。
• 英文摘要： Totally 36 adult albino rats of both sexes were subjected to stereotaxic destruction of either the pontine or the medullary reticular formation. The degenerating reticulospinal fibers consequently produced within the spinal cord have been investigated by Nauta silver impregnation method with reference to the laminar organization of the spinal gray matter described by Rexed [39, 40, 42]. Lesions in the pontine reticular formation caused descending degenerating fibers which formed an intensive ipsilateral and a feeble contralateral tract in the ventral funiculi of either sides of the spinal cord. These fibers were extending the whole length of the spinal cord throughout. Lesions in the medullary reticular formation produced the degenerating fibers descending chiefly in the ipsilateral ventral and lateral funiculi. A few fibers were found in the contralateral ventral funiculus. A decrease in size toward the caudal end was recognized in each fiber bundle because of successive departure of distal part of reticulospinal fibers entering the spinal gray matter. The enlargement regions, particularly, the cervical enlargement segments, received abundant terminal distribution of reticurospinal fibers. The thoracic region was much less intensive, and the sacral region obtained sparse reticulospinal supply. The pontine reticulospinal fibers mainly terminated in the more medial part of the lamina VIII and the adjacent part of the lamina VII. A few seemed to end in the lamina IX. The medullary reticulospinal fibers reached almost the same regions, but extending more laterally somehow. It has been surmised that there might be some direct synaptic connections between the reticulospinal fibers and the dendrites of the ventral horn motoneurons extending from the lamina IX into the lamina VII, other than the direct reticulomotoneuronal connections in the lamina IX. The findings above described suggest that the sites of origin of the reticulospinal fibers of the rat are likely to locate mainly at the medial 2/3 and in a few extent at the lateral 1/3 of the reticular formation of the lower brain stem where the nucleus reticularis pontis caudalis, the nucleus reticularis gigantocellularis, the nucleus reticularis ventralis and the nucleus reticularis lateralis are contained.
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