0000000000025407
AUTHOR
Frank Staub
Glutamate Enhances Brain Damage from Ischemia and Trauma
The amino acid glutamate is a model agent to demonstrate the significance of neurotoxic mediator compounds in secondary brain damage from trauma, ischemia or other adverse conditions. Intensive research of the role of mediator compounds is clinically worthwile as more specific forms of treatment may emerge for the benefit of afflicted patients. In view of the great number of factors, cytokines, etc., which could play a role, it is mandatory that a mediator function in secondary brain damage is identified according to the stringent requirements established for that purpose. Glutamate has been shown — as is the case for only a few other agents — to meet all the criteria of a mediator of secon…
Clearance and metabolism of arachidonic acid by C6 glioma cells and astrocytes.
Effects of increased levels of arachidonic acid (AA) were analyzed in vitro by employment of C6 glioma cells and astrocytes from primary culture. The cells were suspended in a physiological medium added with arachidonic acid (AA) in a concentration range from 0.01 to 0.5 mM. The concentration profiles of the fatty acid and AA-metabolites were subsequently followed for 90 min. AA was measured by gas chromatography, whereas the AA-metabolites PGF2 alpha and LTB4 by radioimmunoassay (RIA). Following administration of AA at 0.05 or 0.1 mM the medium was completely cleared from the fatty acid within 10 to 15 min. However, when 0.5 mM were added, AA concentrations of 0.36 +/- 0.055 mM were found …
Mechanisms of arachidonic acid induced glial swelling
Accumulation of arachidonic acid (AA) in the brain during ischaemia may contribute to development of brain oedema. In this study we investigated the effect of selected drugs on AA-induced cytotoxic brain oedema in C6 glioma cells. Suspended C6 glioma cells were preincubated with drugs and AA (0.1 mM) was added. When no drug was administered cell volume increased immediately after the addition of AA with a maximum cell swelling of 13.1+/-1.9% at 15 min (mean +/- S.E. M.). Preincubation of cells with BW 755C, a dual inhibitor of cyclo- and lipoxygenases, showed no reduction in cell swelling from AA, whereas superoxide dismutase, amiloride and the protein kinase inhibitor H-9370 led to a signi…