Heppelmann B, Messlinger K, Neiss W F, Schmidt R F
Physiologisches Institut, Universität Würzburg, Germany.
Cell Tissue Res. 1994 Mar;275(3):493-501. doi: 10.1007/BF00318818.
The distribution of mitochondria, their content and concentration (expressed as the ratio of the mean volume of mitochondria and the surface of the sensory axon) were determined in group-III and -IV nerve fibres innervating the knee joint capsule in the cat. Mitochondria mainly accumulated in axonal swellings ("beads") and end bulbs of the terminal branches. Between single nerve fibres, marked differences in the content and the concentration of mitochondria were obtained in proximal portions (inside of the perineurium) and in distal portions (unmyelinated sensory endings). In group-III nerve fibres, the mitochondrial concentration ranged from 0.005 to 0.030 microns 3/microns 2 (proximal portion) and from 0.016 to 0.080 microns 3/microns 2 (distal portion). In unmyelinated group-IV nerve fibres, the values also showed a broad variation ranging from 0.001 to 0.011 microns 3/microns 2 (proximal portion) and from 0.003 to 0.019 microns 3/microns 2 (distal portion). The wide range of mitochondrial concentrations may reflect different energy consumption during receptive processes: nerve fibres with a low mechanical threshold and a high probability of excitatory events may be rich in mitochondria, whereas fibres with a high mechanical threshold and a low probability of excitatory events may be poor in mitochondria.
测定了支配猫膝关节囊的Ⅲ组和Ⅳ组神经纤维中线粒体的分布、含量和浓度（以线粒体平均体积与感觉轴突表面积之比表示）。线粒体主要聚集在轴突肿胀（“珠状物”）和终末分支的终球中。在单根神经纤维之间，线粒体的含量和浓度在近端部分（神经束膜内部）和远端部分（无髓感觉末梢）存在显著差异。在Ⅲ组神经纤维中，线粒体浓度在近端部分为0.005至0.030立方微米/平方微米，在远端部分为0.016至0.080立方微米/平方微米。在无髓的Ⅳ组神经纤维中，这些值也有很大变化，在近端部分为0.001至0.011立方微米/平方微米，在远端部分为0.003至0.019立方微米/平方微米。线粒体浓度的广泛范围可能反映了感受过程中不同的能量消耗：机械阈值低且兴奋事件发生概率高的神经纤维可能富含线粒体，而机械阈值高且兴奋事件发生概率低的纤维可能线粒体较少。
