Schlaepfer W W
Brain Res. 1977 Nov 4;136(1):1-9. doi: 10.1016/0006-8993(77)90126-3.
Desheathed segments of rat peripheral nerve were incubated at 37 degrees C in oxygenated Ringer's solution with and without the addition of calcium ionophore, A23187, 10 microgram/ml. Nerve fibers incubated in the presence of both ionophore and calcium revealed extensive granular disintegration of their axonal microtubules and neurofilaments after 30 and 60 min incubation intervals. These changes were not seen following control incubations in Ringer's solution without ionophore or in calcium-free Ringer's solution containing ionophore and EGTA, 1 mmole/1. Ionophore-induced alterations were also noted in Schwann cell cytoplasm. The granular degradative alteration of axoplasm caused by exposure of nerve fibers to ionophore and calcium were believed to be due to an ionophore-mediated influx of calcium into the axoplasm with resultant elevation of intra-axoplasmic calcium concentration. These axoplasmic changes were indistinguishable from the axoplasmic alteration occurring in the distal portions of transpected neurites during Wallerian degeneration. The findings support the view that abnormal calcium influxes are determinants in the degeneration of peripheral nerve.
将大鼠外周神经的去鞘节段在37℃下于通氧的林格氏液中孵育，添加或不添加10微克/毫升的钙离子载体A23187。在同时存在离子载体和钙的情况下孵育的神经纤维，在孵育30分钟和60分钟后，其轴突微管和神经丝出现广泛的颗粒状崩解。在不含离子载体的林格氏液中进行对照孵育，或在含有1毫摩尔/升离子载体和乙二醇双四乙酸（EGTA）的无钙林格氏液中孵育时，均未观察到这些变化。在施万细胞胞质中也注意到了离子载体诱导的改变。神经纤维暴露于离子载体和钙导致的轴浆颗粒状降解改变被认为是由于离子载体介导的钙流入轴浆，导致轴浆内钙浓度升高。这些轴浆变化与沃勒变性期间被切断神经突远端部分发生的轴浆改变无法区分。这些发现支持了异常钙流入是外周神经变性的决定因素这一观点。
