Riva-Depaty I, Fardeau C, Mariani J, Bouchaud C, Delhaye-Bouchaud N
Laboratoire de Neurobiologie du Développement, Institut des Neurosciences (URA 1488), CNRS Université P. et M. Curie, Paris, France.
Exp Neurol. 1994 Jul;128(1):77-87. doi: 10.1006/exnr.1994.1114.
Lesions of the central nervous system result in invasion of peripheral phagocytes and/or in situ activation and proliferation of microglia, depending on the direct or indirect nature of the injury. Neurotoxins which are widely used to induce neurodegeneration have been reported to elicit a pure microglial reaction when administered intraventricularly. However, the mechanical lesion at the injection site, although remote from the lesioned area, could give access to blood-derived cells. Therefore, this study compares the phagocytic reaction occurring after a traumatic lesion of the brain causing a breakdown of the blood-brain barrier (BBB), or after degeneration of the inferior olivary neurons induced by intraperitoneal administration of 3-acetylpyridine, a process that respects the integrity of the BBB as suggested by the results of intravascular injection of Evans blue. The identification of the macrophages at the lesion site used specific binding of the B4 isolectin from Griffonia simplicifolia, preloading of the peripheral monocytes/macrophages with trypan blue, and characteristic morphological features. In traumatically lesioned rats, the lectin-labeled macrophages were mainly large rounded peripheral cells recruited 1-3 days postlesion, whereas in chemically lesioned rats, the cellular reaction appeared 24-36 h postinjection and peaked between 3 and 12 days before undergoing a slow decline. Lectin binding and morphological characteristics indicated that these small cells were reactive microglia. These results confirm that a brain injury leaving the BBB intact involves essentially the recruitment and/or the proliferation of microglia.
中枢神经系统损伤会导致外周吞噬细胞的侵入和/或小胶质细胞的原位激活与增殖，这取决于损伤的直接或间接性质。据报道，广泛用于诱导神经退行性变的神经毒素经脑室内给药时会引发单纯的小胶质细胞反应。然而，注射部位的机械损伤尽管远离损伤区域，却可能使血液来源的细胞进入。因此，本研究比较了在导致血脑屏障（BBB）破坏的脑外伤后，或在腹腔注射3-乙酰吡啶诱导下橄榄核神经元变性后发生的吞噬反应，3-乙酰吡啶诱导下橄榄核神经元变性这一过程如伊文思蓝血管内注射结果所示，保持了血脑屏障的完整性。通过使用来自西非豆的B4异凝集素的特异性结合、用台盼蓝预加载外周单核细胞/巨噬细胞以及特征性形态学特征来鉴定损伤部位的巨噬细胞。在创伤性损伤的大鼠中，凝集素标记的巨噬细胞主要是在损伤后1 - 3天招募的大的圆形外周细胞，而在化学损伤的大鼠中，细胞反应在注射后24 - 36小时出现，并在3至12天达到峰值，随后缓慢下降。凝集素结合和形态学特征表明这些小细胞是反应性小胶质细胞。这些结果证实，在血脑屏障保持完整的情况下，脑损伤主要涉及小胶质细胞的招募和/或增殖。
