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- Document 0873
- DOCN M9620873
- TI HIV-1 gp120 glycoprotein induces [Ca2+]i responses not only in type-2
- but also type-1 astrocytes and oligodendrocytes of the rat cerebellum.
- DT 9602
- AU Codazzi F; Menegon A; Zacchetti D; Ciardo A; Grohovaz F; Meldolesi J;
- Department of Pharmacology, Scientific Institute San Raffaele,; Milan,
- Italy.
- SO Eur J Neurosci. 1995 Jun 1;7(6):1333-41. Unique Identifier : AIDSLINE
- MED/96073242
- AB Cultures of cerebellar cortex cells were exposed to the HIV-1 envelope
- glycoprotein, gp120, and investigated for cytosolic Ca2+ ion
- concentration ([Ca2+]i) changes by the fura-2 ratio videoimaging
- technique while bathed in complete, Na(+)-free or Mg(2+)-free
- Krebs-Ringer media. At the end of the [Ca2+]i experiments the cells were
- fixed and immunoidentified through the revelation of markers specific
- for neurons (microtubule associated protein-2), type-2 (A2B5) or all
- (glial fibrillary acidic protein) astrocytes, oligodendrocytes
- (galactocerebroside) or microglia (F4/80 antibody). In complete medium,
- rapid biphasic (spike-plateau) responses induced by gp120 (0.1-1 nM)
- were observed in a subpopulation of type-2 astrocytes. In addition, slow
- but progressive responses were observed in other type-2 cells and
- oligodendrocytes, whereas type-1 astrocytes showed small responses, if
- any, and granule neurons did not respond at all. Use of Na(+)-free
- medium (a condition that blocked another gp120-induced response,
- cytosolic alkalinization) resulted in an increase in [Ca2+]i response
- that was appreciable not only in type-2 but also in most type-1
- astrocytes, possibly because of the inhibition of the Na+/Ca2+ exchanger
- and the ensuing decrease in Ca2+ extrusion. Granule neurons, including
- those in direct contact with responsive astrocytes, remained
- unresponsive, even when the experiments were carried out in Mg(2+)-free
- medium supplemented with glycine, a condition that favors activation of
- the glutamatergic N-methyl-D-aspartate (NMDA) receptor.(ABSTRACT
- TRUNCATED AT 250 WORDS)
- DE Animal Astrocytes/CLASSIFICATION/*METABOLISM Calcium/*METABOLISM
- Cells, Cultured Cerebellum/CYTOLOGY/*METABOLISM Cytosol/METABOLISM
- HIV Envelope Protein gp120/*PHARMACOLOGY *HIV-1 Immunohistochemistry
- Oligodendroglia/*METABOLISM Osmolar Concentration Rats Rats,
- Sprague-Dawley Support, Non-U.S. Gov't JOURNAL ARTICLE
-
- SOURCE: National Library of Medicine. NOTICE: This material may be
- protected by Copyright Law (Title 17, U.S.Code).
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-