Ashwell K W
School of Anatomy, University of NSW, Kensington, Australia.
Neuropathol Appl Neurobiol. 1992 Dec;18(6):610-8. doi: 10.1111/j.1365-2990.1992.tb00832.x.
The effects of exposure to a cytotoxic agent, methylazoxymethanol acetate (MAM Ac), on the distribution, density and quantitative morphology of microglia in the rat forebrain have been examined with the aid of a peroxidase-conjugated lectin derived from Griffonia simplicifolia. Following exposure to MAM Ac (25 mg/kg maternal body weight) on embryonic day 13 (E13), round microglia were concentrated around the areas of induced cell death at the outer margins of the ventricular germinal zone, particularly in the striatopallidal angle and dorsal thalamus. By E19, there were no detectable differences in microglia distribution between experimental and control animals. The increase in number of microglial cells in the neocortex and caudatoputamen on exposure to MAM Ac lasted for only 4 to 6 days. Subsequently, the number of microglia dropped below control values in both regions. The density of microglia in these areas was similar in control and experimental animals from 6 days after exposure. The proportion of microglia relative to all other cells was also similar at post-natal day 17 (P17) in both experimental and control animals. These results suggest that the distribution and final size of the microglial population is determined by the microenvironment and not by the extent of cell death which may have acted as the initial stimulus to microglial invasion.
利用源自西非豆科植物的过氧化物酶结合凝集素，研究了细胞毒性剂乙酸甲基偶氮甲醇（MAM Ac）对大鼠前脑小胶质细胞分布、密度和定量形态的影响。在胚胎第13天（E13）给母鼠注射MAM Ac（25mg/kg体重）后，圆形小胶质细胞集中在脑室生发区外缘的诱导细胞死亡区域周围，特别是在纹状体苍白球角和背侧丘脑。到E19时，实验动物和对照动物的小胶质细胞分布没有可检测到的差异。暴露于MAM Ac后，新皮层和尾状壳核中小胶质细胞数量的增加仅持续4至6天。随后，这两个区域的小胶质细胞数量降至对照值以下。从暴露后6天起，对照动物和实验动物在这些区域的小胶质细胞密度相似。在出生后第17天（P17），实验动物和对照动物中小胶质细胞相对于所有其他细胞的比例也相似。这些结果表明，小胶质细胞群体的分布和最终大小是由微环境决定的，而不是由可能作为小胶质细胞侵入初始刺激的细胞死亡程度决定的。
