Korean J Physiol Pharmacol.  1997 Aug;1(4):367-376.

Effect of t-butylhydroperoxide on Na+/-dependent glutamate uptake in rabbit brain synaptosome

• Lee HJ
• Kim YK

Abstract

The effect of an organic peroxide, t-butylhydroperoxide (t-BHP), on glutamate uptake was studied in synaptosomes prepared from cerebral cortex. t-BHP inhibited the Na+/-dependent glutamate uptake with no change in the Na+/-independent uptake. This effect of t-BHP was not altered by addition of Ca2+ channel blockers (verapamil, diltiazem and nifedipine) or PLA2 inhibitors (dibucaine, butacaine and quinacrine). However, the effect was prevented by iron chelators (deferoxamine and phenanthroline) and phenolic antioxidants (N,N'-diphenyl-phenylenediamine, butylated hydroxyanisole, and butylated hydroxytoluene). At low concentrations (< 1.0 mM), t-BHP inhibited glutamate uptake without altering lipid peroxidation. Moreover, a large increase in lipid peroxidation by ascorbate/Fe2+ was not accompanied by an inhibition of glutamate uptake. The impairment of glutamate uptake by t-BHP was not intimately related to the change in Na+/-K+/-ATPase activity. These results suggest that inhibition of glutamate uptake by t-BHP is not totally mediated by peroxidation of membrane lipid, but is associated with direct interactions of glutamate transport proteins with t-BHP metabolites. The Ca2+ influx through Ca2+ channel or PLA2 activation may not be involved in the t-BHP inhibition of glutamate transport.

Keyword

t-butylhydroperoxide; Glutamate uptake; Lipid peroxidation; Na+-K+-ATPase activity; Rabbit brain synaptosomes

MeSH Terms

Antioxidants
Brain*
Butylated Hydroxyanisole
Carrier Proteins
Cerebral Cortex
Chelating Agents
Diltiazem
Glutamic Acid*
Iron
Lipid Peroxidation
Membranes
Phenol
Synaptosomes*
tert-Butylhydroperoxide*
Antioxidants
Butylated Hydroxyanisole
Carrier Proteins
Chelating Agents
Diltiazem
Glutamic Acid
Iron
Phenol
tert-Butylhydroperoxide