ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Ascorbate is an essential antioxidant in the CNS, localized predominantly in neuronal cytosol. Slices of mammalian brain rapidly lose ascorbate, however, when incubated in ascorbate-free media; brain slices also take up water and swell. Here we investigated water gain in coronal slices of rat forebrain incubated with and without ascorbate for 1-3 h at 34°C. Slices progressively gained water in ascorbate-free media, with a significant 12% water increase after 3 h at 34°C, compared with the water content of slices after a 1-h recovery period at 24°C, immediately following slice preparation. Inclusion of 400 μM ascorbate in the medium led to an increase in tissue ascorbate content and prevented water gain at 34°C. By contrast, water gain was not inhibited by isoascorbate or thiourea, which are antioxidants that are not accumulated in brain cells. The oxidant H2O2 enhanced water gain, whereas a cocktail of NMDA and non-NMDA receptor blockers inhibited edema formation to the same extent as ascorbate. These data demonstrate that brain edema, linked to glutamate-receptor activation, can result from intracellular oxidative stress and that this can be prevented by ascorbate.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1471-4159.2000.741263.x
Permalink