Maintenance of dorsal horn somatotopic organization and increased high-threshold response after single-root or spared-root deafferentiation in cats.
Maintenance of dorsal horn somatotopic organization and increased high-threshold response after single-root or spared-root deafferentiation in cats.
复制标题
猫单根或备用根传入神经阻滞后维持背角体位组织并增加高阈值反应。
DOI：
10.1152/jn.1982.47.1.103
复制
发表时间：
1982
影响因子：
2.5
通讯作者：
Brenowitz,GL
中科院分区：
文献类型：
--
作者：
Pubols,LM;Brenowitz,GL
I l The somatotopic organization of tactile input to neurons of the L6 dorsal horn of cats was studied electrophysiologically lo-16 wk following partial, unilateral deafferentation. Extracellul ar microelectrode recording was carried out bilaterally in two groups of cats: L6 spared-root animals, in which all dorsal roots caudal to T13 except the L6 root were cut, and L6 single-root animals, in which only the L6 root was cut. The results from the dorsal horn ipsilateral to the lesion were compared with those from the contralateral dorsal horn in each animal. 2. The somatotopic organization of the dorsal horn was similar on two sides of the spinal cord in both spared-root and singleroot animals. Representation of the proximal hindlimb was lost in spared-root animals, but this loss did not change the somatotopic organization of other hindlimb regions. No part of the hindlimb consistently lacked representation in single-root animals. Singleroot deafferentation did, however, lead to a slight mediolateral compression of the map. 3. From these results it was concluded that somatotopic specificity is maintained following these types of partial deafferentation. Any changes in somatotopy are attributable to the complete removal of some inputs. Either the L6 dorsal root alone or all dorsal roots except L6 are capable of maintaining a nearly complete somatotopic map of the L6 dorsal horn. This implies that the inputs from different dorsal roots to the same region of the L6 dorsal horn have spatially similar receptive fields. 4. Both types of partial deafferentation increased the proportion of neurons exhibiting high-threshold input. In spared-root animals this was due to a loss of responsiveness to low-threshold input with maintenance of responsiveness to high-threshold input. In single-root animals, however, there was an absolute increase in neurons responding to high-threshold stimuli. The possible contributions of collateral sprouting and release of afferent inhibition to these effects are discussed.
