title: [Ultrastructural organization of the surface of the cingulate cortex of the cerebrum in rats].
abstract: In the cingulate cortex of rats the marginal glia is predominantly presented as fibrillar astrocytes, their bodies are situated immediately at the surface. Numerous axons, dendrites, synapses and myelinated fibers are often arranged near the very surface and are separated from it with only 1-2 thin processes of glial cells. Along the whole cortical surface one can see a limiting membrane--a layer of non-cellular substance, situating at the distance of 60-100 mcm from plasmalemmas of the marginal astrocytes. Using ruthenium red, it is possible to reveal the glycocalix layer on the surface of the limiting membrane, as well as cords of the electron opaque substance, that connect it with plasmolemma of the superficial astrocytes. Three types of the cingulate cortex surface are described in rats: superficial areas to which cells of the pia mater membrane adjoin; areas where cells of the pia mater membrane are situated at various distance from the cortical surface and areas of close adjoining of the right and left hemispheres of the cerebrum. Sometimes the cleft between the hemispheres is completely reduced, and narrow lamellar-like cells of the pia mater membrane are tightly inserted between the limiting membranes of both hemispheres or adjoin the blood vessel, situating between the hemispheres. At the surface numerous gap and desmosome-like junctions are observed. This is especially important at the border where the media are separated. At injection of neurotoxin 6-hydroxydopamine certain ultrastructural rearrangements are noted in cytoplasm of the marginal astrocytes, changes in the number and extension of intercellular junctions.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000648:ultrastructure; D002462:Cell Membrane / Q000187:drug effects / Q000648:ultrastructure; D006179:Gyrus Cinguli / Q000187:drug effects / Q000648:ultrastructure*; D006892:Hydroxydopamines / Q000633:toxicity; D007365:Intercellular Junctions / Q000187:drug effects / Q000648:ultrastructure; D008854:Microscopy, Electron; D016627:Oxidopamine; D051381:Rats; D011919:Rats, Inbred Strains; D013499:Surface Properties
chemical_list: D006892:Hydroxydopamines; D016627:Oxidopamine
vernacular_title: Ul'trastrukturnaia organizatsiia poverkhnosti poiasnoĭ kory bol'shogo mozga krys.