Triarhou L C, Herndon R M
Br J Exp Pathol. 1985 Jun;66(3):293-301.
The effect of macrophage inactivation on lysolecithin-induced demyelination was studied. Adult rats were pretreated with a single intraperitoneal dose of 200 mg silica quartz dust, which selectively blocks the activity of circulating monocytes. Surgery was performed the following day and 2 microliters of 1% lysolecithin were injected intraspinally. The animals were perfused with aldehydes at 8 to 60 days postoperatively. Tissues were examined by optical and electron microscopy. The injection of lysolecithin produced a localized demyelinating lesion. Myelin debris in controls was phagocytosed by invading macrophages. Axons within the lesion appeared denuded. At later stages remyelination occurred. When animals were pretreated with silica, the macrophage response was remarkably reduced. The clearance of collapsed myelin was delayed. Accumulation of fluid within the sheaths resulted in tissue oedema and persistent spongiform changes. At 28 and 60 days postoperatively, increased fibrillary astrogliosis was observed but did not appear to interfere with remyelination. The findings of this study suggest that (a) active participation of macrophages is essential for the attainment of demyelination in the lysolecithin model and (b) treatment with silica prevents complete demyelination but has no apparent effect on remyelination.
研究了巨噬细胞失活对溶血卵磷脂诱导的脱髓鞘作用的影响。成年大鼠腹腔注射单剂量200mg石英粉尘进行预处理，该粉尘可选择性阻断循环单核细胞的活性。次日进行手术，向脊髓内注射2微升1%的溶血卵磷脂。术后8至60天用醛类灌注动物。通过光学显微镜和电子显微镜检查组织。注射溶血卵磷脂产生了局部脱髓鞘病变。对照组中的髓鞘碎片被侵入的巨噬细胞吞噬。病变内的轴突似乎裸露。在后期发生了再髓鞘化。当动物用二氧化硅预处理时，巨噬细胞反应明显降低。塌陷髓鞘的清除延迟。鞘内液体积聚导致组织水肿和持续的海绵状改变。术后28天和60天，观察到纤维性星形胶质细胞增生增加，但似乎并未干扰再髓鞘化。本研究结果表明：（a）巨噬细胞的积极参与对于溶血卵磷脂模型中脱髓鞘的实现至关重要；（b）二氧化硅治疗可防止完全脱髓鞘，但对再髓鞘化无明显影响。
