Hiura A, Sakamoto Y
Neurosci Lett. 1987 Apr 23;76(1):101-6. doi: 10.1016/0304-3940(87)90200-x.
Studies were made on the quantitative effects of capsaicin on the L4 dorsal roots and their ganglia (DRG) in mice. Capsaicin at a dose of 50 mg/kg was injected s.c. 1-3 times into neonatal mice, while other mice received only vehicle as controls. After capsaicin treatment unmyelinated fibers decreased by 41.3-75.3% compared to controls. After 2 or 3 capsaicin injections there was a greater decrease in unmyelinated fibers than after a single treatment. Capsaicin had most effect on Schwann cell subunit size of more than 13 axons. Reduction of myelinated fibers ranged from 6.1 to 11.6% (mean: 7.9) in 4 mice. A beta and A delta fibers of 4-5 microns diameter were significantly reduced, whereas A delta fibers of less than 2.0 microns diameter were slightly increased. Small DRG neurons (50-500 microns 2 area) decreased by 50.6-77.4% (mean: 69.6) compared to controls. In addition, capsaicin caused a decrease of 14.2-51.6% (mean: 35.2, n = 4) in large-sized neurons (500-1950 microns 2 area). Thus, capsaicin widely affects small and certain types of large neurons as well as unmyelinated and certain myelinated fibers.
对辣椒素对小鼠L4背根及其神经节（背根神经节，DRG）的定量影响进行了研究。将剂量为50mg/kg的辣椒素皮下注射到新生小鼠体内1 - 3次，而其他小鼠仅接受赋形剂作为对照。与对照组相比，辣椒素处理后无髓纤维减少了41.3 - 75.3%。注射2次或3次辣椒素后，无髓纤维的减少比单次处理后更明显。辣椒素对超过13条轴突的施万细胞亚单位大小影响最大。4只小鼠中有髓纤维的减少范围为6.1%至11.6%（平均：7.9%）。直径为4 - 5微米的Aβ和Aδ纤维显著减少，而直径小于2.0微米的Aδ纤维略有增加。与对照组相比，小的背根神经节神经元（面积为50 - 500平方微米）减少了50.6 - 77.4%（平均：69.6%）。此外，辣椒素使大尺寸神经元（面积为500 - 1950平方微米）减少了14.2 - 51.6%（平均：35.2%，n = 4）。因此，辣椒素广泛影响小的和某些类型的大神经元以及无髓和某些有髓纤维。
