Benowitz L I, Goldberg D E, Madsen J R, Soni D, Irwin N
Department of Neurosurgery, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Proc Natl Acad Sci U S A. 1999 Nov 9;96(23):13486-90. doi: 10.1073/pnas.96.23.13486.
The purine nucleoside inosine has been shown to induce axon outgrowth from primary neurons in culture through a direct intracellular mechanism. For this study, we investigated the effects of inosine in vivo by examining whether it would stimulate axon growth after a unilateral transection of the corticospinal tract. Inosine applied with a minipump to the rat sensorimotor cortex stimulated intact pyramidal cells to undergo extensive sprouting of their axons into the denervated spinal cord white matter and adjacent neuropil. Axon growth was visualized by anterograde tracing with biotinylated dextran amine and by immunohistochemistry with antibodies to GAP-43. Thus, inosine, a naturally occurring metabolite without known side effects, might help to restore essential circuitry after injury to the central nervous system.
嘌呤核苷次黄嘌呤已被证明可通过直接的细胞内机制诱导培养的原代神经元长出轴突。在本研究中，我们通过检查在单侧切断皮质脊髓束后它是否会刺激轴突生长，来研究次黄嘌呤在体内的作用。用微型泵将次黄嘌呤施加到大鼠感觉运动皮层，刺激完整的锥体细胞使其轴突广泛发芽，进入去神经支配的脊髓白质和相邻的神经毡。通过用生物素化葡聚糖胺进行顺行示踪以及用抗GAP - 43抗体进行免疫组织化学来观察轴突生长。因此，次黄嘌呤这种天然存在且无已知副作用的代谢物，可能有助于在中枢神经系统损伤后恢复基本的神经回路。
