       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).

