Matthews M A
Cell Tissue Res. 1977 Apr 20;179(3):413-27. doi: 10.1007/BF00221111.
Sprague-Dawley albino rats ranging in age from neonate to 60 days postnatal (dpn)were subjected to cortical extirpations encompassing the SmI somato-sensory projection fields of neurons in the ventrobasal (VB) complex. Eectron microscopy of this region reveals degenerative changes in VB neurons, the rate and severity of which is inversely proportional to the age of the animal (Matthews et al., 1977). Numerous, distinctive non-neuronal elements, similar to those infiltrating the perivascular space of some vessels in the area, rapidly accumulate within the zone of degeneration in animals lesioned between 0 and 9 dpn. These display dense, heterochromatin nuclei, concentrations of of free ribosomes and rosettes, and pleomorphic dense bodies which become more evident as further reactive transformations accompany the phagocytic incorporation of degenerating neuronal remnants. Other non-neuronal elements exhibit a euchromatin nucleus, bundles of microtubules, and fewer free ribosomes. Such cells are also capable of phagocytosis and production of dense bodies. Both variants are comparable in appearance to the "M" cells of previous reports (Matthews and Kruger, 1973b). Cortical lesions of older animals result in the appearance of "M" cells in VB; however, the population densities observed in the immature VB are not achieved. Conversely, astrocytic hypertrophy, associated with the increased incidence of degenerating boutons in the more mature animal, represents a prominent response to injury which does not occur to a significant extent in younger animals. Morphological criteria for determining the nature of some "M" cells are given for a discussion of their presumptive derivation from various mesodermal progenitors and a brief consideration of other hypothesized origins.
选用出生至出生后60天（dpn）的Sprague-Dawley白化大鼠，对其进行皮质切除，切除范围包括腹侧基底（VB）复合体中神经元的SmI体感投射区域。该区域的电子显微镜检查显示VB神经元有退行性变化，其变化速率和严重程度与动物年龄成反比（Matthews等人，1977年）。许多独特的非神经元成分，类似于该区域某些血管周围间隙中的浸润成分，在出生后0至9天接受损伤的动物的退变区域内迅速积聚。这些成分显示出致密的异染色质核、游离核糖体和玫瑰花结的聚集，以及多形性致密小体，随着吞噬退变神经元残余物的进一步反应性转变，这些小体会变得更加明显。其他非神经元成分则表现为常染色质核、微管束和较少的游离核糖体。这类细胞也能够进行吞噬作用并产生致密小体。这两种变体在外观上与先前报道的“M”细胞相当（Matthews和Kruger，1973b）。年龄较大动物的皮质损伤会导致VB中出现“M”细胞；然而，未成熟VB中观察到的细胞群密度并未达到。相反，在更成熟动物中，与退变终末增多相关的星形细胞肥大是对损伤的一种突出反应，在较年轻动物中这种反应并不明显。给出了确定某些“M”细胞性质的形态学标准，以讨论它们可能来自各种中胚层祖细胞的情况，并简要考虑其他假设的起源。
