Regeneration of monoamine-containing axons in the developing and adult spinal cord of the rat following intraspinal 6-OH-dopamine injections or transections
Regeneration of monoamine-containing axons in the developing and adult spinal cord of the rat following intraspinal 6-OH-dopamine injections or transections
复制标题
脊髓内注射 6-OH-多巴胺或横断后，大鼠发育中和成年脊髓中含单胺轴突的再生
DOI：
10.1007/bf00305627
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
A. Seiger
中科院分区：
文献类型：
--
作者：
L. Nygren;L. Olson;A. Seiger
在个体发育过程中以及在机械或化学、6-羟基多巴胺（6-OH-DA）诱导、轴突切断、用Falck-Hillarp荧光组织化学法研究了大鼠海马神经元的单胺类神经递质，主要的NA和5-HT轴突束和终末神经支配区在出生时就已经存在，并且在两周后达到基本成熟的神经支配模式。HT和NA神经在远段是通过横断脊髓获得的。在未成熟和成熟的动物中，切断的单胺纤维发芽到坏死区和瘢痕组织中是旺盛的，但再生到远段是非常差的。通过局部椎管内注射6-OH-DA，获得下行NA轴突和终末的选择性变性。因此，5-HT纤维系统以及脊髓的所有其他部分都完好无损。因此，该方法应证明是有用的，用于评估的NA和5-HT神经元系统在脊髓的确切功能role. Reinervation的脊髓远侧部由新的NA纤维后6-OH-DA诱导的去神经支配的描述。这个过程在年轻动物中更快，但也发生在成年动物中。目前的证据表明，神经再支配主要是轴突切断的纤维向下生长的结果，但生长在侧支发芽的形式，从一些可能幸存的纤维在远端区域也可能作出贡献。神经再支配导致正常的神经支配模式在1-这表明，文献中经常报道的脊髓横断后许多脊神经束的再生不良是由于神经元因素如瘢痕组织和受损的循环而不是神经本身，因为NA神经在机械横断后的神经再支配非常差，但在机械横断后的神经再生良好。化学的6-OH-DA诱导的轴突切断
SummaryGrowth of descending noradrenaline (NA) and 5-hydroxytryptamine (5-HT) axons in the rat spinal cord during ontogenesis and following mechanical or chemical, 6-hydroxydopamine (6-OH-DA) induced, axotomy, was studied with the Falck-Hillarp histochemical fluorescence method for monoamines.The major NA and 5-HT axon bundles and terminal innervation areas are present already at birth and an essentially mature pattern of innervation is reached after two weeks.Complete degeneration of both 5-HT and NA nerves in the distal segment is obtained by a transection of the spinal cord. Sprouting of the cut monoamine fibers into the necrotic zone and scar tissue is vigorous in both immature and mature animals, but regeneration into the distal segment is very poor.Selective degeneration of the descending NA axons and terminals is obtained by a localized intraspinal 6-OH-DA injection. Thus, the 5-HT fiber systems as well as all other parts of the spinal cord are left intact. The method should therefore prove useful for evaluating the exact functional role of the NA and 5-HT neuron systems in the spinal cord.Reinnervation of the distal part of the spinal cord by new NA fibers following 6-OH-DA induced denervation is described. This process is faster in younger animals but takes place also in adult animals. The present evidence suggests that reinnervation mainly is the result of downgrowth of the axotomized fibers, but growth in the form of collateral sprouting from a few possibly surviving fibers in the distal region may also contribute. Reinnervation lead to a normal innervation pattern within 1–2 months in the various age groups.It is suggested that the poor regeneration of many spinal nerve tracts often reported in the literature following transection of the spinal cord is due to extraneuronal factors such as scar tissue and impaired circulation rather than to the nerves per se since reinnervation by NA nerves was very poor following mechanical transection but good following chemical, 6-OH-DA-induced axotomy.
影响因子：
1.3
作者：
Riema Abdunnur
通讯作者：
Riema Abdunnur