Summary
The ultrastructural appearances of microglia in the rat cerebral cortex were examined following experimental cold lesions. It was found that microglia toop up extravascularized plasma by pinocytosis. These pinocytotic vesicles coalesced to form large vacuoles of medium electron density, which subsequently decreased in size and increased in density and morphological complexity. Concurrently the microglial cells underwent dedifferentiation and division. Between 3 and 7 days after making the cold lesion it was difficult to distinguish between phagocytes of microglial and haematogenous origin. The relationship of microglia to haematogenous phagocytes is discussed.
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Adrian, E. K.: Cell division in injured spinal cord. Amer. J. Anat.123, 501–520 (1968).
—, Walker, B. E.: Incorporation of thymidine-H3 by cells of normal and injured mouse spinal cord. J. Neuropath. exp. Neurol.21, 597–609 (1962).
Bakay, L., Haque, I.: Morphological and chemical studies in cerebral edema. I. Cold induced edema. J. Neuropath. exp. Neurol.23, 393–418 (1964).
Bignami, A., Ralston III, H. J.: The cellular reaction to Wallerian degeneration in the central nervous system of the cat. Brain Res.13, 444–461 (1969).
Blakemore, W. F.: The fate of escaped plasma protein after thermal necrosis of the rat brain: An electron microscope study. J. Neuropath. exp. Neurol.28, 139–152 (1969a).
—: The ultrastructure of the subependymal plate in the rat. J. Anat. (Lond.)104, 423–433 (1969b).
Blakemore, W. F.: Reaction of neuroglia and microglia to injury. Ph. D. Thesis, London 1969c.
—: The ultrastructural appearance of astrocytes following thermal lesions of the rat cortex. J. Neurol. Sci.12, 319–332 (1971).
—, Cavanagh, J. B.: Neuroaxonal dystrophy occurring in an experimental “dying back” process in the rat. Brain92, 789–804 (1969).
Blinzinger, K., Hager, H.: Elektronenmikroskopische Untersuchungen zur Feinstruktur ruhender und progressiver Mikrogliazellen im Z.N.S. des Goldhamsters. In: Topics of basic neurology. Progress in Brain Research. Vol. 6, p. 99 eds. W. Bargmann and J. P. Schadé. New York-London-Amsterdam: Elsevier Publ. 1964.
—, Kreutzberg, G.: Displacement of synaptic terminals from regenerating motoneurons by microglial cells. Z. Zellforsch.85, 145–157 (1968).
Bunge, R. P.: Glial cells and the central myelin sheath. Physiol. Rev.48, 197–251 (1968).
Cohn, Z. A.: The regulation of pinocytosis in mouse macrophages. I. Metabolic requirements as defined by the use of inhibitors. J. exp. Med.124, 557–571 (1966).
—, Benson, B.: The differentiation of mononuclear phagocytes. Morphology, cytochemistry and biochemistry. J. exp. Med.121, 153–170 (1965a).
——: The in-vitro differentiation of mononuclear phagocytes. I. The influence of inhibitors and the results of autoradiagraphy. J. exp. Med.121, 279–287 (1965b).
——: The in-vitro differentiation of mononuclear phagocytes. II. The influence of serum on granule formation, hydrolase production and pinocytosis. J. exp. Med.121, 835–848 (1965c).
Huntington, H. W., Terry, R. D.: The origin of the reactive cells in cerebral stab wounds. J. Neuropath. exp. Neurol.25, 646–653 (1966).
King, L. S.: Vital staining of microglia. Arch. Path.19, 656–672 (1935).
Klatzo, I., Miquel, J.: Observations on pinocytosis in nervous tissue. J. Neuropath. exp. Neurol.19, 475–487 (1960).
— Wiśniewski, H., Smith, D. E.: Observations on penetration of serum proteins into the central nervous system. In: Biology of neuroglia. Progress in Brain Research, Vol. 15, pp. 73–88, eds. E. P. D. De Robertis and R. Carrea. London-New York-Amsterdam: Elsevier Publ. 1965.
Königsmark, B. W., Sidman, R. L.: Origin of brain macrophages in the mouse. J. Neuropath. exp. Neurol.22, 643–676 (1963).
Mori, S., Leblond, C. P.: Identification of microglia in light and electron microscopy. J. comp. Neurol.135, 57–79 (1969).
Mugnaini, E., Walberg, F.: Ultrastructure of neuroglia. Ergebn. Anat. Entwickl.-Gesch.37, 194–236 (1964).
Robbins, E., Jentzsch, G., Nicali, A.: The centriole cycle in synchronised Hela cells. J. Cell Biol.36, 329–339 (1968).
Rubinstein, L. J., Klatzo, I., Miquel, J.: Histochemical observations in oxidative enzyme activity of glial cells in a local brain injury. J. Neuropath. exp. Neurol.21, 116–136 (1962).
Torvik, A., Skjörten, F.: Electron microscopic observations in nerve cell regeneration and degeneration after axon lesions. II. Changes in the glial cells. Acta neuropath. (Berl.)17, 265–282 (1971).
Vaughn, J. E., Hinds, P. L., Skoff, R. P.: Electron microscopic studies of Wallerian degeneration in rat optic nerves. I. The multipotential glia. J. comp. Neurol.140, 175–205 (1970).
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This work was carried out at the M.R.C. Research Group in Applied Neurobiology, Institute of Neurology, Queens Square, London.
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Blakemore, W.F. Microglial reactions following thermal necrosis of the rat cortex: An electron microscope study. Acta Neuropathol 21, 11–22 (1972). https://doi.org/10.1007/BF00687996
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DOI: https://doi.org/10.1007/BF00687996