Webber C L, Pleschka K
Pflugers Arch. 1976 Jul 30;364(2):113-21. doi: 10.1007/BF00585178.
Intracellular recording and staining techniques were applied to the study of cat phrenic motoneurons. Spontaneously driven phrenic cells possessed individualistic depolarization and spiking patterns that were a function of the conduction velocity in the different motor axons. Staining of phrenic motoneurons with Procion yellow indicated that fast conducting cells with small slow-wave depolarizations were large in size while slow conducting cells with large depolarizations were small in size. This implicated differences in membrane input resistance between large and small cells, although an unequal distribution of inputs to the individual components could not be discounted. On the average, phrenic motoneurons had a smaller dendritic surface area and smaller dendritic dominance than lumbosacral motoneurons. These factors help to explain the higher membrane resistances and longer time constants of phrenic cells. Phrenic dendrites were found to project in all directions away from the cell body and form ellipsoidal receptive fields that overlapped with other phrenic fields. It is speculated that the close approximation of phrenic dendrites with one another could, in part, be responsible for the high degree of synchronization among the different phrenic units.
细胞内记录和染色技术被应用于猫膈运动神经元的研究。自发驱动的膈神经细胞具有独特的去极化和放电模式，这些模式是不同运动轴突传导速度的函数。用普施安黄对膈运动神经元进行染色表明，具有小的慢波去极化的快速传导细胞体积较大，而具有大的去极化的慢传导细胞体积较小。这意味着大小细胞之间膜输入电阻存在差异，尽管不能排除单个成分输入分布不均的情况。平均而言，膈运动神经元的树突表面积和树突优势度比腰骶运动神经元小。这些因素有助于解释膈神经细胞较高的膜电阻和较长的时间常数。发现膈神经树突从细胞体向各个方向投射，并形成与其他膈神经场重叠的椭圆形感受野。据推测，膈神经树突彼此紧密接近可能部分是不同膈神经单位之间高度同步的原因。
