Innervation of regenerated spindles in muscle grafts of the rat.
Innervation of regenerated spindles in muscle grafts of the rat.
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大鼠肌肉移植物中再生纺锤体的神经支配。
DOI：
10.1007/bf00495009
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Staffeld,CG
中科院分区：
文献类型：
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作者：
Walro,JM;Kucera,J;Cui,F;Staffeld,CG
本文通过对大鼠趾长伸肌（趾长伸肌）移植物和正常趾长伸肌的10 μm冰冻切片进行酶染色，观察了移植物和正常趾长伸肌肌梭的神经供应和肌梭包裹纤维的特点。再生纺锤体中的分枝纤维比对照纺锤体中的多。48%的再生梭接受感觉神经支配。传入神经支配的Spendulum有一个更大的轴周空间比没有传入神经支配的纺锤体。传入神经支配的再生纤维的横截面积小，赤道区与肌原纤维局限于周边的纤维，不可预测的模式的不均匀和不可逆的染色沿着长度的纤维的“肌原纤维”腺苷三磷酸酶（mATPase）酸和碱性预孵育后。与此相反，再生纤维缺乏感觉神经支配类似的梭外纤维，因为它们通常表现出整个长度的纤维，没有中央聚集的肌核，均匀染色的mATPase和逆转染色的mATPase预孵育后，在酸性或碱性介质。大约30%的包裹纤维缺乏感觉神经支配染色类似于I型梭外纤维，染色模式从未观察到在梭内纤维的正常纺锤体。所有显示这种染色模式的封装纤维组反映，这些纤维可能已被支配的骨骼运动轴突，最初支配I型梭外纤维的侧支，或仅梭运动神经元支配的纤维表达类似于梭外纤维的感觉神经支配的情况下的mATP酶的染色模式。感觉神经支配也可能影响再生的梭内纤维上运动末梢的多个部位的重建。有感觉神经支配的再生纤维比无感觉神经支配的再生纤维具有更多的运动终末。mATP酶的染色模式以及传入神经支配的纤维和无感觉神经支配的纤维之间的运动末梢的数量反映了传入神经可以影响肌细胞的分化和运动神经支配的重建，而不是在产前晚期。生后早期肌梭形成和分化。
Features of the nerve supply and the encapsulated fibers of muscle spindles were assessed in grafted and normal extensor digitorum longus (EDL) muscles of rats by analysis of serial 10-μm frozen transverse sections stained for enzymes which delineated motor and sensory endings, oxidative capacity and muscle fiber type.The number of fibers was significantly more variable, and branched fibers were more frequently observed in regenerated spindles than in control spindles. Forty-eight percent of regenerated spindles received sensory innervation. Spindles reinnervated by afferents had a larger periaxial space than did spindles which were not reinnervated by afferents. Regenerated fibers innervated by afferents had small cross-sectional areas, equatorial regions with myofi-brils restricted to the periphery of fibers, unpredictable patterns of nonuniform and nonreversible staining along the length of the fiber for ‘myofibrillar’ adenosine triphosphatase (mATPase) after acid and alkaline preincubation. In contrast, regenerated fibers devoid of sensory innervation resembled extrafusal fibers in that they usually exhibited myofibrils throughout the length of the fiber, no central aggregations of myonuclei, uniform staining for mATPase and a reversal of staining for mATPase after preincubation in an acid or alkaline medium. Approximately thirty percent of encapsulated fibers devoid of sensory innervation stained analogous to a type I extrafusal fiber, a pattern of staining never observed in intrafusal fibers of normal spindles. Groups of encapsulated fibers all exhibiting this pattern of staining reflect that either these fibers may have been innervated by collaterals of skeletomotor axons that originally innervated type I extrafusal fibers or that fibers innervated by only fusimotor neurons express patterns of staining for mATPase similar to extrafusal fibers in the absence of sensory innervation. Sensory innervation may also influence the reestablishment, of multiple sites of motor endings on regenerated intrafusal fibers. Those regenerated fibers innervated by afferents had more motor endings than did regenerated fibers devoid of sensory innervation.Differences in size, morphology, and patterns of staining for mATPase and numbers of motor endings between fibers innervated by afferents and fibers devoid of sensory innervation reflect that afferents can influence the differentiation of muscle cells and the reestablishment of motor innervation other than during the late prenatal/early postnatal period when muscle spindles form and differentiate in rats.