Oztürk G, Tonge D A
Neuroscience Research Centre, Guy's Hospital, London, SE1 9RT, United Kingdom
Exp Neurol. 2001 Jun;169(2):376-85. doi: 10.1006/exnr.2001.7667.
Synthesis of leukemia inhibitory factor (LIF) is increased in lesioned peripheral nerves and it is thought that this may cause increased expression of galanin (GAL) in axotomized dorsal root ganglia (DRG) neurons and also to promote axonal regeneration. We therefore compared effects of LIF and nerve growth factor (NGF) on galanin expression and axonal growth using cultured intact DRGs of adult mice. In control lumbar DRGs cultured for 3 days, only 16% of neurons were immunoreactive for GAL, but this was increased to 38% in preparations cultured with LIF. NGF by itself had no effect on GAL expression, but the proportion of GAL-positive neurons in cultures incubated with LIF and NGF together (22%) was less than that observed in DRGs cultured with LIF alone. Similar results were obtained using thoracic DRGs. In collagen gels, NGF caused marked increases in the numbers and lengths of outgrowing axons as observed in previous studies. In contrast, LIF did not stimulate axonal outgrowth but increased the proportions of axons which were immunoreactive for GAL. The results indicate that expression of LIF in lesioned nerves may affect expression of neuropeptides such GAL rather than stimulating axonal regeneration.
损伤的周围神经中白血病抑制因子（LIF）的合成增加，据认为这可能导致轴突切断的背根神经节（DRG）神经元中甘丙肽（GAL）表达增加，并促进轴突再生。因此，我们使用成年小鼠培养的完整DRG比较了LIF和神经生长因子（NGF）对甘丙肽表达和轴突生长的影响。在培养3天的对照腰段DRG中，只有16%的神经元对GAL呈免疫反应性，但在用LIF培养的制剂中，这一比例增加到了38%。单独使用NGF对GAL表达没有影响，但同时用LIF和NGF培养的培养物中GAL阳性神经元的比例（22%）低于单独用LIF培养的DRG中观察到的比例。使用胸段DRG也获得了类似的结果。在胶原凝胶中，与先前研究中观察到的一样，NGF导致长出的轴突数量和长度显著增加。相比之下，LIF没有刺激轴突生长，但增加了对GAL呈免疫反应性的轴突比例。结果表明，损伤神经中LIF的表达可能影响诸如GAL等神经肽的表达，而不是刺激轴突再生。
