Three‐dimensional structure of astrocytes in the rat dentate gyrus
Tóm tắt
Structural features of astrocytes in the rat dentate gyrus were studied by means of light and high‐voltage electron microscopy of Golgi‐impregnated materials, conventional electron microscopy, combined Golgi‐electron microscopy, and immunohistochemistry for glial fibrillar acidic protein.
Astrocytes in the dentate gyrus were of the protoplasmic type and were classified into six subtypes based on the location of their somata: i.e., astrocytes 1) in the polymorph layer, (2) in the subgranular zone, (3) in the granular cell layer, (4) at the border of the granular cell layer and the molecular layer, (5) in the molecular layer, and (6) subjacent to the pia surface.
Stereoscopic observations of 5‐μm‐thick sections of Golgi‐impregnated materials revealed three‐dimensional structural details of astroglial processes not apparent in either the light microscope or in conventional thinsection electron microscopy. Most of them were basically thin sheets, varying in shape and size in accordance with their sites. In the granule cell layer, thin veillike sheets or lamellae, originating from three kinds of astrocytes (subtypes 2, 3, and 4), intervened between granule cell somata, whereas in the plexiform and molecular layers small leafletlike appendages originating from astrocytes (subtypes 1, 2, 4, and 5) intermingled with one another, making spongelike conglomerates. Thus astrocytes in the subgranular zone and those at the border of the granule cell layer and the molecular layer showed prominent regional differentiation of their processes among layers. In addition to these sheetlike processes, thin threadlike processes were also common.
Từ khóa
Tài liệu tham khảo
Gardner‐Medwin A. R., 1981, Possible roles of vertebrate neuroglia in potassium dynamics, spreading depression and migraine, J. Exp. Biol., 95, 111, 10.1242/jeb.95.1.111
Glees P., 1955, Neuroglia, Morphology and Function
Hama K., 1979, Purkinje cell and related neurons and glia cells under high‐voltage electron microscopy, Prog. Neuropathol., 4, 61
Hama K., 1978, Fine structure of the Müller cell revealed by high‐voltage electron microscopy, Sens. Proc., 2, 296
Klatzo I., 1952, A study of glia by the Golgi method, Lab. Invest., 1, 345
Kuffler S. W., 1966, The physiology or neuroglial cells, Ergebn. Physiol., 57, 1, 10.1007/BF02259903
Penfield W., 1932, Cytology and Cellular Pathology of the Nervous System, 423
Peters A., 1976, The fine structure of the nervous system: The neurons and supporting cells
Polak M., 1965, Progress in Brain Research Vol. 15, Biology of Neuroglia, 12
Rakic P., 1981, The Organization of the Cerebral Cortex, 7
Ramón y Cajal S., 1909, Histologie du système nerveux de l'homme et des vertébrés, 10.5962/bhl.title.48637
Ramón y Cajal S., 1911, Histologie du systeme nerveux de l'homme et des vertébrés
Sternberger L. A., 1979, Immunocytochemistry
Varon S. S., 1979, Neuron‐glia interactions, Neurosci. Res. Prog. Bull., 17, 1
West R. W., 1972, Superficial warming of epoxy blocks for cutting of 25‐150 μm sections to be resectioned in the 40‐90 nm range, Stain Technol., 47, 201, 10.3109/10520297209116485
Wilson C. J., 1983, Three‐dimensional structure of dendritic spines in the rat neostriatum, J. Neurosci., 3, 383, 10.1523/JNEUROSCI.03-02-00383.1983