Nolte C, Schachner M, Martini R
Department of Neurobiology, University of Heidelberg, Federal Republic of Germany.
J Neurocytol. 1989 Dec;18(6):795-808. doi: 10.1007/BF01187232.
The immunocytochemical localization of the neural cell adhesion molecules L1, N-CAM and J1/tenascin was investigated by light and electron microscopical techniques in murine Pacinian corpuscles during development, in the adult and in the regenerating state. In adult corpuscles, L1 was present only at contact sites between the sensory axon and inner core lamellae. From birth, the earliest stage tested, until day 7, L1 was additionally expressed on lamellar processes of the inner core cells. N-CAM was expressed in developing and adult corpuscles on lamellae and somata of the inner and outer core cells at their contact sites but was hardly detectable at contact sites between axolemma and inner core lamellae. J1/tenascin was found only in association with the extracellular material of the inner core, especially with the two radial clefts and the boundary space between inner and outer core. In developing corpuscles, J1/tenascin became detectable on extracellular material with the onset of inner core differentiation at approximately day 2. After transection or crush of the sciatic nerve, L1 disappeared from the corpuscles but reappeared with regrowing axons at contact sites between axonal membranes and inner core cells. At any regenerative stage inner core cells remained L1-negative. In denervated and reinnervated corpuscles the expression pattern of N-CAM and J1/tenascin did not differ from the normal adult. These observations suggest that a sensory organ, the Pacinian corpuscle, differs from the sciatic nerve and the neuromuscular junction in that its expression of adhesion molecules remains the same in the denervated state as in the innervated adult. Furthermore, in the denervated Pacinian corpuscle, adhesion molecule expression does not resemble that of any developmental stage tested. Thus, other cures than regulation of adhesion molecule expression patterns might be involved in the successful reinnervation of sensory corpuscles.
运用光镜和电镜技术，对发育过程中、成年期及再生状态下的小鼠帕西尼小体进行研究，以确定神经细胞黏附分子L1、N-CAM和J1/腱生蛋白的免疫细胞化学定位。在成年小体中，L1仅存在于感觉轴突与内核板层之间的接触部位。从出生（测试的最早阶段）到第7天，L1在内核细胞的板层突起上也有表达。N-CAM在发育中的和成年小体的内、外核细胞的板层和胞体的接触部位有表达，但在轴膜与内核板层之间的接触部位几乎检测不到。J1/腱生蛋白仅在内核的细胞外物质中发现，尤其是与两条放射状裂隙以及内、外核之间的边界间隙有关。在发育中的小体中，随着内核在大约第2天开始分化，在细胞外物质上可检测到J1/腱生蛋白。坐骨神经横断或挤压后，L1从小体中消失，但随着轴突再生，在轴突膜与内核细胞之间的接触部位重新出现。在任何再生阶段，内核细胞均保持L1阴性。在去神经和重新神经支配的小体中，N-CAM和J1/腱生蛋白的表达模式与正常成年小体无异。这些观察结果表明，作为一种感觉器官，帕西尼小体与坐骨神经和神经肌肉接头不同，其黏附分子的表达在去神经状态下与成年神经支配状态相同。此外，在去神经的帕西尼小体中，黏附分子的表达与所测试的任何发育阶段均不同。因此，感觉小体成功的重新神经支配可能涉及除调节黏附分子表达模式之外的其他机制。
