THE SOMATOTOPIC ORGANIZATION OF PRIMARY AFFERENT TERMINALS IN THE SUPERFICIAL LAMINAE OF THE DORSAL HORN OF THE RAT SPINAL-CORD
THE SOMATOTOPIC ORGANIZATION OF PRIMARY AFFERENT TERMINALS IN THE SUPERFICIAL LAMINAE OF THE DORSAL HORN OF THE RAT SPINAL-CORD
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DOI：
10.1002/cne.902310106
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发表时间：
1985-01-01
影响因子：
2.5
通讯作者：
WOOLF, CJ
中科院分区：
文献类型：
--
作者：
SWETT, JE;WOOLF, CJ
利用小麦胚芽凝集素结合的辣根过氧化物酶（WGA-HRP）的经神经节转运，揭示了支配大鼠后腿的外周神经初级传入纤维末梢的中心分布。在单独的实验中，通过电生理记录技术确定了每条用WGA-HRP标记的神经的皮肤外周感受野的大小和位置。通过数字图像分析，外围感受野的大小和位置与来自这些感受野的初级传入神经末梢所占据的浅表背角区域相关。数据来自大腿后皮神经、腓外侧神经、腓腓神经、隐神经、腓浅神经和胫神经。坐骨神经、腓肠神经、腓外侧神经、腓浅神经和胫神经的分支分别投射到背浅角的一个独立而独特的区域，并共同形成一个u形的末端标记区，从腰椎L2段延伸到L5的尾端。U间隙从L2延伸至L3-4边界，由隐神经末梢占据。总的来说，供应后肢的所有初级传入神经占据了浅背角内侧的3/4，胫骨神经的末端位于最内侧，占据了所有末端野中最大的。腓浅神经的传入神经位于胫骨内侧区和腓肠外侧区之间。后皮神经的传入神经位于尾部和外侧。来自后皮神经和隐神经的末梢野与其他神经的末梢野不同，它们具有分裂的表征，这可能是由于它们靠近肢体中轴线所致。每个神经的外周和中枢表征的比较显示，1平方毫米的浅表背角表面积服务于大约600-900平方毫米的有毛皮肤和大约300平方毫米的无毛皮肤。在背角中观察到的绝大多数末端标记位于边缘层和明胶质，这表明小直径传入神经具有有序的促生长排列，其中皮肤表面的每个部分都由传入纤维支配，这些传入纤维在背角内的首选部位终止。
Transganglionic transport of wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP) was used to reveal the central distribution of terminals of primary afferent fibers from peripheral nerves innervating the hind leg of the rat. In separate experiments the sizes and locations of cutaneous peripheral receptive fields were determined by electrophysiological recording techniques for each of the nerves that had been labeled with WGA-HRP. By using digital image analysis, the sizes and positions of the peripheral receptive fields were correlated with the areas of superficial dorsal horn occupied by terminals of primary afferents from each of these receptive fields. Data were obtained from the posterior cutaneous nerve of the thigh, lateral sural, sural, saphenous, superficial peroneal, and tibial nerves. The subdivisions of the sciatic nerve, the sural, lateral sural, superficial peroneal, and tibial nerves each projected to a separate and distinct region of the superficial dorsal horn and collectively formed a U-shaped zone of terminal labeling extending from lumbar spinal segments L2 to the caudal portions of L5. The gap in the U extended from L2 to the L3-4 boundary and was occupied by terminals from the saphenous nerve. Collectively, all primary afferents supplying the hindlimb occupied the medial 3/4 of the superficial dorsal horn with terminals from the tibial nerve lying most medially and occupying the largest of all the terminal fields. Afferents from the superficial peroneal lay in a zone between the medially situated tibial zone and the more laterally placed sural zone. Afferents from the posterior cutaneous nerve were located most caudally and laterally. Terminal fields from the posterior cutaneous and saphenous nerves differed from the others in having split representations caused presumably by their proximity to the mid-axial line of the limb. Comparisons between the peripheral and the central representations of each nerve revealed that 1 mm2 of surface area of the superficial dorsal horn serves approximately 600-900 mm2 of hairy skin and roughly 300 mm2 of glabrous skin. The vast majority of terminal labeling observed in the dorsal horn was found in the marginal layer and substantia gelatinosa, suggesting that small diameter afferents have an orderly somatotropic arrangement in which each portion of the skin surface is innervated by afferent fibers that terminate in preferred localities within the dorsal horn.