Kaur C, Chan Y G, Ling E A
Department of Anatomy, Faculty of Medicine, National University of Singapore.
J Hirnforsch. 1992;33(6):645-52.
An epidural application of kainic acid (KA) over the cerebral cortex in rat resulted in an extensive lesion in the ipsilateral cerebral cortex. This procedure elicited an accumulation of a large number of macrophages at the site of lesion covering a period of 4 weeks beginning 4 days after the KA application. The macrophages in the centre of lesion were characterized by abundant cytoplasm containing a variable number of lysosomes and phagosomes. Neurons at the same site were depleted during the period examined. They underwent degeneration following the KA treatment. With the monoclonal antibodies OX-42, OX-18 and OX-6, intense immunoreactivity was observed in these cells at the light and electron microscopic levels. Besides these antibodies, the cells were stained positively with the isolectin Griffonia simplicifolia (GSAI-B4). At the periphery of the lesion, many cells bearing the external morphology of microglia were also intensely stained with the GSAI-B4 and the monoclonal antibodies. It was concluded from this study that neuronal degeneration, caused by the excitotoxin KA, induced the accumulation of macrophages which exhibited CR3 receptors (marked by OX-42), MHC I antigen (marked by OX-18) and MHC Ia (marked by OX-6). The expression of these surface antigens may be related to their active phagocytic activity. The reaction with GSAI-B4 indicates the presence of specific lectin receptors on the macrophages which would serve a similar function. The present lectin histochemistry and immunohistochemical studies suggest that macrophages in the centre of the KA-induced lesion were derived from infiltrated monocytes while those at the periphery originated from the activation of local microglial cells.
在大鼠大脑皮层硬膜外应用海藻酸（KA）会导致同侧大脑皮层出现广泛损伤。该操作引发了大量巨噬细胞在损伤部位的聚集，从KA应用后4天开始，持续4周。损伤中心的巨噬细胞特征是细胞质丰富，含有数量不等的溶酶体和吞噬体。在所检查的时间段内，同一部位的神经元减少。它们在KA处理后发生变性。使用单克隆抗体OX - 42、OX - 18和OX - 6，在光镜和电镜水平下均观察到这些细胞有强烈的免疫反应性。除了这些抗体外，这些细胞还用异凝集素西非单叶豆（GSAI - B4）染色呈阳性。在损伤周边，许多具有小胶质细胞外形的细胞也被GSAI - B4和单克隆抗体强烈染色。从这项研究得出的结论是，由兴奋性毒素KA引起的神经元变性诱导了巨噬细胞的聚集。这些巨噬细胞表现出CR3受体（由OX - 42标记）、MHC I抗原（由OX - 18标记）和MHC Ia（由OX - 6标记）。这些表面抗原的表达可能与其活跃的吞噬活性有关。与GSAI - B4的反应表明巨噬细胞上存在特定的凝集素受体，其功能类似。目前的凝集素组织化学和免疫组织化学研究表明，KA诱导损伤中心的巨噬细胞来源于浸润的单核细胞，而周边的巨噬细胞则来源于局部小胶质细胞的激活。
