Large diameter primary afferent input is required for expression of the Cat-301 proteoglycan on the surface of motor neurons.
Large diameter primary afferent input is required for expression of the Cat-301 proteoglycan on the surface of motor neurons.
复制标题
Cat-301 蛋白多糖在运动神经元表面的表达需要大直径的初级传入输入。
DOI：
10.1016/0306-4522(90)90148-w
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发表时间：
1990
期刊：
影响因子：
3.3
通讯作者：
Hockfield,S
中科院分区：
文献类型：
--
作者：
Kalb,RG;Hockfield,S
由单克隆抗体Cat-301识别的细胞表面蛋白聚糖的表达受生命早期神经元活动的调节。在这里，我们报告的Cat-301蛋白聚糖运动神经元的表达依赖于初级传入输入在出生后早期。以前，我们表明，在两个不同的系统中，Y-细胞在猫外侧膝状体核和运动神经元在仓鼠脊髓，Cat-301抗原的表达需要在一个有限的发展时期的神经元活动。在出生后早期破坏Y细胞（通过黑暗饲养或单眼眼睑缝合）或运动神经元（通过坐骨神经挤压或脊髓损伤）的活性可阻止Cat-301表达。破坏成年人的神经元活动对Cat-301表达没有影响。Cat-301表达的开始对应于活动依赖性发育期的结束，为了进一步解剖Cat-301在运动神经元上表达所需的节段性反射弧的组成部分，在这里，我们评估了背根切断的传入神经阻滞的影响。在成年动物中，传入神经阻滞后两周，所有坐骨运动神经元继续表达Cat-301。相反，在新生儿中，在传入神经阻滞后两周，Cat-301的正常发育表达减少，并且不到50%的坐骨运动神经元表达Cat-301。接下来，我们使用神经毒素辣椒素选择性地损伤小直径传入神经。与神经根切断术相反，新生儿小直径传入神经的缺失对Cat-301在运动neurons.These结果表明，大直径初级传入神经（可能是那些传递肌肉和/或关节信息的传入神经）传递的输入对早期运动神经元的正常成熟没有影响。它们还为运动神经元的活动依赖性成熟提供了进一步的证据。
The expression of a cell surface proteoglycan, recognized by monoclonal antibody Cat-301, is regulated by neuronal activity in early life. Here we report that the expression of the Cat-301 proteoglycan on motor neurons depends on primary afferent input in the early postnatal period. Previously we showed that in two different systems, Y-cells in the cat lateral geniculate nucleus and motor neurons in the hamster spinal cord, the expression of the Cat-301 antigen requires neuronal activity during a circumscribed period in development. Disrupting the activity of Y-cells (by dark rearing or by monocular lid suture) or of motor neurons (by sciatic nerve crush or by spinal cord lesion) during the early postnatal period prevents Cat-301 expression. Disrupting neuronal activity in adults has no effect on Cat-301 expression. The onset of Cat-301 expression corresponds to the end of the period of activity-dependent development.In order to further dissect the components of the segmental reflex arc required for the expression of Cat-301 on motor neurons, here we evaluated the effect of deafferentation by dorsal rhizotomy. In adult animals two weeks after deafferentation all sciatic motor neurons continue to express Cat-301. In contrast, in neonates two weeks after deafferentation the normal developmental expression of Cat-301 is reduced and less than 50% of sciatic motor neurons express Cat-301. We next selectively lesioned the small diameter afferents using the neurotoxin capsaicin. In contrast to rhizotomy, neonatal deletion of small diameter afferents has no effect on the development of Cat-301 expression on motor neurons.These results imply that input relayed by large diameter primary afferents (probably those conveying muscle and/or joint information) is required for normal maturation of motor neuronal properties during early life. They also provide further evidence for activity-dependent maturation of motor neurons.