Emergence of Serotonergic Neurons After Spinal Cord Injury in Turtles.
Emergence of Serotonergic Neurons After Spinal Cord Injury in Turtles.
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DOI：
10.3389/fncir.2018.00020
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发表时间：
2018
影响因子：
3.5
通讯作者：
Russo RE
中科院分区：
文献类型：
--
作者：
Fabbiani G;Rehermann MI;Aldecosea C;Trujillo-Cenóz O;Russo RE
神经回路的可塑性表现为多种形式，在调节行为适应需求变化的同时保持稳定性方面发挥着重要作用。例如，在脊髓发育过程中，神经元中的神经递质身份会随着脊髓网络活动的变化而动态调整。我们有理由推测，这种类型的可塑性也可能发生在成熟的脊髓回路中，以应对损伤。由于5 -羟色胺能信号在脊髓功能中起核心作用，我们假设淡水龟（Trachemys scripta elegans）的脊髓损伤可能引发5 -羟色胺能神经支配的稳态变化。为了验证这种可能性，我们对血清素（5-HT）和脊髓损伤前后血清素能表型相关的关键分子进行了免疫组织化学检测。我们发现，在损伤后的急性期，密集的5 -羟色胺能神经支配明显减少。然而，在脊髓损伤后30天，5-羟色胺能细胞（5-HT+）的数量在损伤部位的尾端增加。这些细胞表达神经元标记物HuC/D和转录因子Nkx6.1。新的5-羟色胺能神经元不含胸腺嘧啶类似物5-溴-2 ' -脱氧尿苷（BrdU），也不表达增殖细胞核抗原（PCNA），这表明新的5-羟色胺能神经元不是新生的，而是有丝分裂后改变了其神经化学特性的细胞。向5 -羟色胺能神经递质表型转换可能是一种脊髓稳态机制，以补偿5 -羟色胺能神经调节下降的损失，从而帮助海龟表现出出色的功能恢复。5-HT1A受体激动剂（±）-8-羟基-2-二丙胺四溴化萘（8-OH-DPAT）阻断了5-HT+细胞的增加，表明5-HT1A受体可能触发了再规范过程。
Plasticity of neural circuits takes many forms and plays a fundamental role in regulating behavior to changing demands while maintaining stability. For example, during spinal cord development neurotransmitter identity in neurons is dynamically adjusted in response to changes in the activity of spinal networks. It is reasonable to speculate that this type of plasticity might occur also in mature spinal circuits in response to injury. Because serotonergic signaling has a central role in spinal cord functions, we hypothesized that spinal cord injury (SCI) in the fresh water turtle Trachemys scripta elegans may trigger homeostatic changes in serotonergic innervation. To test this possibility we performed immunohistochemistry for serotonin (5-HT) and key molecules involved in the determination of the serotonergic phenotype before and after SCI. We found that as expected, in the acute phase after injury the dense serotonergic innervation was strongly reduced. However, 30 days after SCI the population of serotonergic cells (5-HT+) increased in segments caudal to the lesion site. These cells expressed the neuronal marker HuC/D and the transcription factor Nkx6.1. The new serotonergic neurons did not incorporate the thymidine analog 5-bromo-2′-deoxyuridine (BrdU) and did not express the proliferating cell nuclear antigen (PCNA) indicating that novel serotonergic neurons were not newborn but post-mitotic cells that have changed their neurochemical identity. Switching towards a serotonergic neurotransmitter phenotype may be a spinal cord homeostatic mechanism to compensate for the loss of descending serotonergic neuromodulation, thereby helping the outstanding functional recovery displayed by turtles. The 5-HT1A receptor agonist (±)-8-Hydroxy-2-dipropylaminotetralin hydrobromide (8-OH-DPAT) blocked the increase in 5-HT+ cells suggesting 5-HT1A receptors may trigger the respecification process.
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影响因子：
5.3
作者：
Branchereau, P;Chapron, J;Meyrand, P
通讯作者：
Meyrand, P
影响因子：
4.6
作者：
Craven, SE;Lim, KC;Rosenthal, A
通讯作者：
Rosenthal, A
影响因子：
2.5
作者：
LAMOTTE, CC;JOHNS, DR;DELANEROLLE, NC
通讯作者：
DELANEROLLE, NC
影响因子：
25
作者：
Pattyn, A;Simplicio, N;Brunet, JF
通讯作者：
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储备池神经元发射器解答：新型神经可塑性。
影响因子：
3
作者：
Dulcis, Davide;Spitzer, Nicholas C.
通讯作者：
Spitzer, Nicholas C.