Schoen S W, Graeber M B, Tóth L, Kreutzberg G W
Department of Neuromorphology, Max-Planck-Institute for Psychiatry, Martinsried n. Munich, F.R.G.
Brain Res. 1988 Mar 1;467(1):125-36. doi: 10.1016/0165-3806(88)90074-0.
The distribution of the ectoenzyme 5'-nucleotidase was studied in the developing rat cerebellum using enzyme- and immunocytochemical techniques in order to evaluate its appearance in the processes of cellular migration during nervous system development. 5'-Nucleotidase enzymatic activity appeared first in the external granular layer (postnatal day 6). Then, the inner portion of the external granular layer and the developing molecular layer became prominently stained (postnatal day 12). At 21 days the adult pattern was established with a diffuse labeling of the whole molecular layer. Additionally, 5'-nucleotidase enzymatic activity was found around Purkinje cells. At the ultrastructural level migrating nerve cells exhibited an intense surface labeling whereas resting neuroblasts of the external granular layer as well as all post-migratory nerve cells were negative. Immunocytochemistry differed from enzyme histochemistry in that immunoreactivity was found to be selectively associated with glial elements. It is suggested that 5'-nucleotidase may serve as a marker for processes of neuronal migration and neuron-glia interactions during postnatal ontogeny. Underlying mechanisms could be due to an interaction of 5'-nucleotidase with the extracellular matrix molecule, laminin, and cytoskeletal actin involved in locomotion.
利用酶和免疫细胞化学技术研究了发育中大鼠小脑中外切酶5'-核苷酸酶的分布，以评估其在神经系统发育过程中细胞迁移过程中的出现情况。5'-核苷酸酶的酶活性首先出现在外颗粒层（出生后第6天）。然后，外颗粒层的内部和发育中的分子层开始显著染色（出生后第12天）。在21天时，建立了成年模式，整个分子层呈现弥漫性标记。此外，在浦肯野细胞周围发现了5'-核苷酸酶的酶活性。在超微结构水平上，迁移的神经细胞表现出强烈的表面标记，而外颗粒层的静止神经母细胞以及所有迁移后的神经细胞均为阴性。免疫细胞化学与酶组织化学的不同之处在于，免疫反应性被发现与神经胶质成分选择性相关。有人提出，5'-核苷酸酶可能作为出生后个体发育过程中神经元迁移和神经元-神经胶质相互作用过程的标志物。潜在机制可能是由于5'-核苷酸酶与细胞外基质分子层粘连蛋白以及参与运动的细胞骨架肌动蛋白相互作用所致。
