HETEROGENEITY IN THE DISTRIBUTION AND MORPHOLOGY OF MICROGLIA IN THE NORMAL ADULT-MOUSE BRAIN
HETEROGENEITY IN THE DISTRIBUTION AND MORPHOLOGY OF MICROGLIA IN THE NORMAL ADULT-MOUSE BRAIN
复制标题
DOI：
10.1016/0306-4522(90)90229-w
复制
发表时间：
1990-01-01
期刊：
影响因子：
3.3
通讯作者：
GORDON, S
中科院分区：
文献类型：
--
作者：
LAWSON, LJ;PERRY, VH;GORDON, S
我们已经研究了小胶质细胞在正常成年小鼠脑中的分布，使用免疫细胞化学检测巨噬细胞特异性质膜糖蛋白F4/80。我们有兴趣了解小胶质细胞在成年人大脑中的分布是否与发育过程中细胞死亡的幅度和单核细胞募集的区域变化有关，或者成年人的分布是否受到其他局部微环境因素的影响。我们通过研究小胶质细胞在不同脑区的形态，进一步研究了小胶质细胞对其微环境敏感的可能性。小胶质细胞大量存在于大脑的所有主要部分，但分布不均匀。不同区域之间免疫染色的小胶质细胞突起的密度有五倍以上的变化。灰质中的小胶质细胞比白色多。特别是，密集的区域包括海马体，嗅端脑，基底神经节和黑质。相比之下，密度较低的区域包括纤维束，小脑和脑干的大部分。大脑皮层、丘脑和下丘脑具有平均细胞密度。发育性细胞死亡的数量和小胶质细胞的成人分布之间没有简单的关系。成年小鼠脑中小神经胶质细胞总数的估计为3.5 × 10 - 6。106，与肝脏中发现的重量相当。然而，小胶质细胞拥有高达两倍的枯否细胞膜表面积，枯否细胞是肝脏的大型常驻巨噬细胞。小胶质细胞的比例从皮质和胼胝体的5%到黑质的12%不等。小胶质细胞的形态根据它们的位置而变化。他们大致分为三类。紧凑的细胞是圆形的细胞，有时有一个或两个短而厚的肢，生有短的突起（“刚毛”）。它们类似于肝脏的枯否细胞，并且仅在缺乏血脑屏障的部位发现。在纤维束中发现有纵向分支的细胞，并具有几个长突起，这些突起通常平行于或偶尔垂直于神经纤维的纵轴排列。放射状分支的细胞遍布整个神经鞘。它们可以是极其精细的，并且在过程分支的长度和复杂性方面存在很大差异。在成年CNS中没有单核细胞样细胞的证据。小胶质细胞形态的系统性变化进一步证明了这些细胞对它们的微环境敏感。
We have examined the distribution of microglia in the normal adult mouse brain using immunocytochemical detection of the macrophage specific plasma membrane glycoprotein F4/80. We were interested to learn whether the distribution of microglia in the adult brain in related to regional variation in the magitude of cell death during development and resulting monocyte recruitment, or whether the adult distribution is influenced by other local microenvironmental cues. We further investigated the possibility that microglia are sensitive to their microenvironment by studying their morphology in different brain regions. Microglia are present in large numbers in all major divisions of the brain but are not uniformly distributed. There is a more than five-fold variation in the density of immunostained microglial processes between different regions. More microglia are found in gray matter than white. Particularly, densely populated areas include the hippocampus, olfactory telencephalon, basal ganglia and substantia nigra. In comparison, the less densely populated areas include fibre tracts, cerebellum and much of the brainstem. The cerebral cortex, thalamus and hypothalamus have average cell densities. There was no simple relationship between the amount of developmental cell death and the adult distribution of microglia. An estimate of the total number of microglia in the adult mouse brain, 3.5 .times. 106, is comparable to that found in the liver on a weight for weight basis. However, microglia possess up to twice the surface area of membrane of Kupffer cells, the large resident macrophages of the liver. The proportion of cells that were microglia varied from 5% in the cortex and corpus callosum, to 12% in the substantia nigra. Microglia vary in morphology depending on their location. They were broadly classified into three categories. Compact cells are rounded cells, sometimes with one or two short thick limbs, bearing short processes ("bristles"). They resemble Kupffer cells of the liver and are found exclusively in sites lacking a blood-brain barrier. Longitudinally branched cells are found in fibre tracts and possess several long processes which are usually aligned parallel to, or more occasionally perpendicular to, the longitudinal axis of the nerve fibres. Radially branched cells are found throughout the neuropil. They can be extremely elaborate and there is wide variation in the length and complexity of branching of the processes. There was no evidence of monocyte-like cells in the adult CNS. The systematic variation in microglial morphology provides further evidence that these cells are sensitive to their microenvironment.