Sango Kazunori, Yanagisawa Hiroko, Takaku Shizuka
Division of Neural Development and Regeneration, Department of Developmental Morphology, Tokyo Metropolitan Institute for Neuroscience, 2-6 Musashidai, Fuchu-shi, Tokyo 183-8526, Japan.
Histochem Cell Biol. 2007 Jul;128(1):35-43. doi: 10.1007/s00418-007-0290-x. Epub 2007 May 23.
Ciliary neurotrophic factor (CNTF) is abundantly expressed in Schwann cells in adult mammalian peripheral nerves, but not in neurons. After peripheral nerve injury, CNTF released from disrupted Schwann cells is likely to promote neuronal survival and axonal regeneration. In the present study, we examined the expression and histochemical localization of CNTF in adult rat DRG in vivo and in vitro. In contrast to the restricted expression in Schwann cells in vivo, we observed abundant CNTF mRNA and protein expression in DRG neurons after 3 h, 2, 7, and 15 days in dissociated cell culture. At later stages (7 and 15 days) of culture, CNTF immunoreactivity was detected in both neuronal cell bodies and regenerating neurites. These results suggest that CNTF is synthesized and transported to neurites in cultured DRG neurons. Since we failed to observe CNTF immunoreactivity in DRG neurons in explant culture, disruption of cell-cell interactions, rather than the culture itself, may be an inducible factor for localization of CNTF in the neurons.
睫状神经营养因子（CNTF）在成年哺乳动物外周神经的施万细胞中大量表达，但在神经元中不表达。外周神经损伤后，受损施万细胞释放的CNTF可能促进神经元存活和轴突再生。在本研究中，我们检测了成年大鼠背根神经节（DRG）中CNTF在体内和体外的表达及组织化学定位。与体内施万细胞中有限的表达不同，我们在解离细胞培养3小时、2天、7天和15天后，观察到DRG神经元中大量的CNTF mRNA和蛋白表达。在培养后期（7天和15天），在神经元细胞体和再生神经突中均检测到CNTF免疫反应性。这些结果表明，CNTF在培养的DRG神经元中合成并运输到神经突。由于我们在外植体培养的DRG神经元中未观察到CNTF免疫反应性，细胞间相互作用的破坏而非培养本身，可能是CNTF在神经元中定位的诱导因素。
