Colombo J A, Lipina S, Yáñez A, Puissant V
Programa Unidad de Neurobiología Aplicada (PRUNA) (CEMIC-CONICET), Buenos Aires, Argentina.
Int J Dev Neurosci. 1997 Nov;15(7):823-33. doi: 10.1016/s0736-5748(97)00043-9.
Long astroglial processes traversing several cortical laminae appear to be characteristic of primate brains. Whether interlaminar processes develop as a modification of radial glia or are truly postnatal elements stemming from stellate astroglia, could be assessed by analyzing their early developmental stages. A survey of glial fibrillar acidic protein immunoreactive (GFAP-IR) astroglial interlaminar processes in the cerebral cortex of Ceboidea monkeys at various postnatal developmental ages, and in human cortical samples of a ten day and a seven year old child disclosed that such processes develop postnatally. At one month of age GFAP-IR interlaminar processes in monkeys were scarce and short in most frontal, parietal or occipital (striate) cortical areas, except for sulcal (principal and orbital sulci) and temporal cortical areas. Some processes were weakly positive for vimentin, and these were most abundant in ventral temporal cortical areas. At two months of age processes were present in all these areas, albeit in restricted patches and significantly shorter than in adults. The expression of this pattern was increased at seven months of age. At three years of age almost every area showed abundant processes and with lengths comparable to the adult Ceboidea individuals. In humans, at 10 days of age long interlaminar processes were readily apparent in a frontal cortex sample, becoming most apparent at the age of seven years although not reaching yet the adult characteristics as described previously.
(1) GFAP-IR interlaminar processes develop postnatally, thus typifying a subtype of the classical stellate forms; (2) they bear no obvious direct relationship with radial glia; (3) their development is not contemporary among the various cortical regions. These long cellular processes represent an addition to those already described for other astroglial cell types in the adult mammalian brain (Golgi-Bergmann glia, tanicytes, Muller cells).
贯穿多个皮质层的长星形胶质细胞突起似乎是灵长类动物大脑的特征。层间突起是作为放射状胶质细胞的一种变异而发育形成，还是真正源自星状星形胶质细胞的出生后形成的成分，可通过分析其早期发育阶段来评估。对不同出生后发育年龄的阔鼻猴大脑皮质以及一名10天大和一名7岁儿童的人类皮质样本中胶质纤维酸性蛋白免疫反应性（GFAP-IR）星形胶质细胞层间突起的调查显示，此类突起是在出生后发育的。在1月龄时，除了脑沟（主要脑沟和眶沟）和颞叶皮质区域外，阔鼻猴额叶、顶叶或枕叶（纹状）皮质区域中GFAP-IR层间突起稀少且短小。一些突起波形蛋白呈弱阳性，且在腹侧颞叶皮质区域最为丰富。在2月龄时，所有这些区域均有突起，尽管呈局限的斑块状且明显短于成年猴。这种模式的表达在7月龄时增加。在3岁时，几乎每个区域都显示有丰富的突起，其长度与成年阔鼻猴个体相当。在人类中，在10日龄时，长层间突起在额叶皮质样本中很明显，在7岁时最为明显，尽管尚未达到先前描述的成年特征。
（1）GFAP-IR层间突起在出生后发育，因此是经典星状形态的一种亚型；（2）它们与放射状胶质细胞没有明显的直接关系；（3）它们在不同皮质区域的发育并不同步。这些长细胞突起是对成年哺乳动物大脑中已描述的其他星形胶质细胞类型（高尔基-贝格曼胶质细胞、束状细胞、米勒细胞）的补充。
