ULTRASTRUCTURAL-CHANGES OF THE CENTRAL SCALLOPED (C-1) PRIMARY AFFERENT ENDINGS OF SYNAPTIC GLOMERULI IN THE SUBSTANTIA-GELATINOSA-ROLANDI OF THE RAT AFTER PERIPHERAL NEUROTOMY
ULTRASTRUCTURAL-CHANGES OF THE CENTRAL SCALLOPED (C-1) PRIMARY AFFERENT ENDINGS OF SYNAPTIC GLOMERULI IN THE SUBSTANTIA-GELATINOSA-ROLANDI OF THE RAT AFTER PERIPHERAL NEUROTOMY
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DOI：
10.1007/bf01188402
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发表时间：
1990-06-01
期刊：
影响因子：
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通讯作者：
ARVIDSSON, J
中科院分区：
文献类型：
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作者：
CASTROLOPES, JM;COIMBRA, A;ARVIDSSON, J
切断三个主要前肢神经3天后，在大鼠脊髓C6-C7节段的I型突触肾小球的深色扇形中央C1末端中观察到精细的结构变化。由于突触小泡数量减少，同侧 26% 的 C1 末端表现出较浅的外观。单位截面积的突触小泡数量仅为对侧正常C1末梢的42%。每个肾小球中 C1 末端与其周围轮廓的突触接触数量减少，神经胶质包络增加至 C1 末端轮廓的 15%。至第12天，囊泡和突触损失逐渐加剧，胶质细胞并置增多，但未观察到明显的胶质细胞吞噬迹象。从第 3 天到第 12 天，改变的 C1 末端数量增加，而看起来正常的 C1 末端数量减少。后者在第 12 天消失，改变的在第 15 天消失，从这个阶段开始，I 型 golmeruli 不再出现在治疗侧。华勒变性特征的电子致密变性鲍顿变化的缺乏为跨神经节变性过程中凝胶质中一致发现的嗜银结构的缺乏或极少量提供了解释。 C1 终端的逐渐衰退引发了它们的命运问题。未来使用稳定标记物的研究可能会提供答案。
Fine structural changes were observed in the dark scalloped central C1 terminals of type I synaptic glomeruli in spinal cord segments C6-C7 of the rat 3 days after cutting the three main forelimb nerves. Twenty-six percent of the C1 terminals occurring on the ipsilateral side showed a lighter appearance due to a decrease in the number of synaptic vesicles. The number of synaptic vesicles per unit section area was only 42% of that present in normal C1 terminals on the contralateral side. The number of synaptic contacts of C1 terminals with the profiles surrounding them in each glomerulus was diminished and glial envelopment was increased to 15% of C1 terminal contour. Up to day 12, vesicle and synaptic losses were gradually aggravated and glial apposition was increased, but no obvious signs of glial engulfment were observed. From day 3 to day 12, altered C1 terminals increased in number, while those that appeared normal decreased. The latter had disappeared at day 12 and the altered ones at day 15, and from this stage type I golmeruli were no longer present on the treated side. The lack of electron-dense degenerative bouton changes characteristic of Wallerian degeneration offers an explanation for the lack of or minimal amount of argyrophilic structures which has been found consistently in the substantia gelatinosa during transganglionic degeneration. The gradual decay of the C1 terminals raises the question of their fate. Future studies with the use of a stable marker might provide an answer.