Institut des Sciences du Mouvement, Etienne-Jules MAREY, UMR CNRS 6233, Université de la Méditerranée (Aix-Marseille II,Aix-Marseille Université), Parc Scientifique et Technologique de Luminy, Faculté des Sciences du Sport de Marseille, 13288 Marseille Cedex 09, France.
Neuroscience. 2011 Aug 11;188:182-92. doi: 10.1016/j.neuroscience.2011.04.066. Epub 2011 May 7.
We previously demonstrated that vitamin D₂ (ergocalciferol) triggers axon regeneration in a rat model of peripheral nerve transection. In order to confirm the regenerative potential of this neuroactive steroid, we performed a study in which vitamin D₃ (cholecalciferol) was delivered at various doses to paralytic rats. After spinal cord compression at the T10 level, rats were given orally either vehicle or vitamin D₃ at the dose of 50 IU/kg/day or 200 IU/kg/day. Three months later, M and H-waves were recorded from rat Tibialis anterior muscle in order to quantify the maximal H-reflex (H(max)) amplitude. We also monitored the ventilatory frequency during an electrically induced muscle fatigue known to elicit the muscle metaboreflex and an increase in respiratory rate. Spinal cords were then collected, fixed and immunostained with an anti-neurofilament antibody. We show here that vitamin D-treated animals display an increased number of axons within the lesion site. In addition, rats supplemented with vitamin D₃ at the dose of 200 IU/kg/day exhibit (i) an improved breathing when hindlimb was electrically stimulated; (ii) an H-reflex depression similar to control animals and (iii) an increased number of axons within the lesion and in the distal area. Our data confirm that vitamin D is a potent molecule that can be used for improving neuromuscular adaptive mechanisms and H-reflex responses.
我们之前已经证明，维生素 D₂（麦角钙化醇）可触发周围神经横断大鼠模型中的轴突再生。为了确认这种神经活性甾体的再生潜力，我们进行了一项研究，在该研究中，以不同剂量向麻痹大鼠给予维生素 D₃（胆钙化醇）。在 T10 水平脊髓受压后，大鼠经口给予载体或维生素 D₃，剂量为 50 IU/kg/天或 200 IU/kg/天。三个月后，从大鼠胫骨前肌记录 M 和 H 波，以量化最大 H 反射（H(max)）幅度。我们还监测了已知可引起肌肉代谢反射和呼吸频率增加的电诱导肌肉疲劳期间的通气频率。然后收集脊髓，用抗神经丝抗体固定并免疫染色。我们在这里表明，维生素 D 处理的动物在病变部位显示出更多的轴突。此外，以 200 IU/kg/天剂量补充维生素 D₃的大鼠表现出：（i）后肢电刺激时呼吸改善；（ii）H 反射抑制类似于对照动物；以及（iii）病变部位和远端区域内的轴突数量增加。我们的数据证实，维生素 D 是一种有效的分子，可用于改善神经肌肉适应机制和 H 反射反应。
