Wilson P, Meyers D E, Snow P J
J Neurophysiol. 1986 Mar;55(3):604-17. doi: 10.1152/jn.1986.55.3.604.
The somatotopic organization of spinocervical tract cells and unidentified dorsal horn neurons that lie in the same depth range as the spinocervical tract cells has been examined in detail in the lumbosacral enlargement of cats anesthetized with alpha-chloralose. Only gentle hair movement or light touch of glabrous skin were used as stimuli. Within the region of the dorsal horn containing these neurons there is a precise somatotopic organization. However, there is considerable variation between animals in the relationship between the somatotopic map and the lumbosacral segmental boundaries. The somatotopic map described here is considered to be restricted to a 300- to 500-micron thick lamina. In the medial half to two-thirds of this lamina in the L6 and L7 segments the toes are represented in a rostrocaudal sequence from toe 2 to toe 5. Over the most medial 200-500 micron of this part of the dorsal horn are found cells that respond to stimulation of the glabrous skin of the toe pads and the central pad. The toe representation is surrounded by a strip of foot representation, which is in turn surrounded by a strip of leg representation. The most lateral part of the lamina curves ventrally in the L6 and L7 segments and contains a continuous rostrocaudal representation of the skin of the thigh. In this region are found both spinocervical tract cells and unidentified dorsal horn neurons with receptive fields on the thigh. The skin of the hindlimb is represented such that a line of discontinuity runs down the posteromedial thigh, leg, and foot. Skin lateral to this line is represented caudally, while skin medial to it is represented rostrally.
在用α-氯醛糖麻醉的猫的腰骶膨大处，已详细研究了脊髓颈束细胞以及与脊髓颈束细胞位于相同深度范围内的未明确的背角神经元的躯体定位组织。仅使用轻柔的毛发移动或对无毛皮肤的轻触作为刺激。在包含这些神经元的背角区域内，存在精确的躯体定位组织。然而，在不同动物之间，躯体定位图与腰骶节段边界之间的关系存在相当大的差异。此处描述的躯体定位图被认为局限于一个300至500微米厚的板层。在L6和L7节段该板层的内侧一半至三分之二区域，脚趾以从第2趾到第5趾的前后顺序排列。在背角这部分最内侧的200至500微米范围内，发现了对趾垫和中央垫无毛皮肤刺激有反应的细胞。脚趾的代表区域被一条足部代表带包围，而这条足部代表带又被一条腿部代表带包围。在L6和L7节段，板层的最外侧部分向腹侧弯曲，包含大腿皮肤的连续前后代表区。在这个区域发现了脊髓颈束细胞和在大腿上有感受野的未明确的背角神经元。后肢皮肤的代表方式是，一条不连续线沿大腿后内侧、小腿和足部向下延伸。这条线外侧的皮肤在尾侧代表，而内侧的皮肤在前侧代表。
