SOMATOTOPIC ORGANIZATION OF EXTERNAL CUNEATE NUCLEUS IN ALBINO-RATS
SOMATOTOPIC ORGANIZATION OF EXTERNAL CUNEATE NUCLEUS IN ALBINO-RATS
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DOI：
10.1016/0006-8993(74)90801-4
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发表时间：
1974-01-01
期刊：
影响因子：
2.9
通讯作者：
WELKER, W
中科院分区：
文献类型：
--
作者：
CAMPBELL, SK;PARKER, TD;WELKER, W
在麻醉、去小脑白化大鼠的楔状外核(EC)内描绘了肌肉感受区的表达模式。使用球头钨微电极和紧密间距的电极穿孔系统地探索了这个核。记录单个神经元，并通过自然刺激大鼠暴露于前部的肌肉来确定其激活感受区的外周来源和方式。在31只动物的411个穿刺点上记录的585个单位中，243个单位定位于EC，并被同侧前肌的低阈值牵拉或点状压力所激活。所有经组织学验证明确定位于EC内的细胞仅从位于肌肉的感受区被激活。在EC的三维范围内，周围投射的肌肉组织模式相当详细，颈部肌肉出现在其吻侧极，手臂和肩部肌肉更靠近尾侧，前臂和手部肌肉逐渐向尾侧。位于不同解剖节段的肌肉的表达没有重叠。感受野识别确定的EC单位总是从单个肌肉激活。然而，那些不能准确识别其视野的单位可能从不同的肌肉获得了会聚的激活(或抑制)，而我们的程序不允许我们检测到这些肌肉。EC中没有一个单位是从皮肤感受野激活的，我们也没有发现皮肤和肌肉感受野激活的汇聚。EC细胞从未从后肢或对侧前肢的感受区被激活。
The pattern of representation of muscle receptive fields was delineated in the external cuneate nucleus (EC) of anesthetized, cerebellectomized albino rats. This nucleus was explored systematically using ball-tipped tungsten microelectrodes and closely-spaced electrode punctures. Single neurons were recorded from and the peripheral source and modality of their activating receptive fields were identified using natural stimulation of exposed muscles of the rat's forequarter. Each muscle was stimulated by pulling the tendon, pressure to its belly with fine probes and/or by stretch induced by joint rotation.Of 585 single units recorded from 411 punctures in 31 animals, 243 were localized to EC and were activated by stretch at low threshold or punctate pressure of muscles of the ipsilateral forequarter. All cells definitely localized within EC by histological verification were activated only from receptive fields located in muscle. The musculotopic pattern of organization of peripheral projections within the three-dimensional confines of EC was rather detailed, with neck muscles represented in its rostrolateral pole, arm and shoulder muscles more caudomedially, and forearm and hand muscles progressively more caudally. There was no overlap of representations from muscles located in different anatomical segments. EC units for which receptive field identification was certain were always activated from a single muscle. However, those units whose fields could not be identified precisely may have received convergent activation (or inhibition) from different muscles which our procedures did not allow us to detect. No units in EC were activated from cutaneous receptive fields, nor did we find convergence of activation from cutaneous and muscle receptive fields. EC cells were never activated from receptive fields in the hindlimb or contralateral forelimb.