Superoxide radical generation in rat striatal slices: Effects of depolarization and calcium ion deficiency conditions

Abstract

Objective: Oxidative stress is thought to be responsible for neurotoxicity through the generation of oxygen radicals. The aim of the current study was to determine the generation of superoxide radicals under depolarization conditions in rat striatal slices. We also investigated the effect of intracellular and extracellular calcium ion concentrations on superoxide radical formation. Methods: Striatal slices were obtained using a vibroslicer and after incubation of slices in appropriate incubation media the formation of superoxide radicals was detected by the chemiluminescence technique using a luminometer. Results: Depolarization conditions (50 mM-K+) were used to induce superoxide radical generation in striatal slices. Under depolarization conditions lactate dehydrogenase activity (LDH) was also increased. Incubation of striatal slices in calcium chelator EGTA and intracellular calcium release blocker ryanodine increased superoxide generation compared to depolarization conditions. Conclusion: Under calcium ion deficiency conditions, increased superoxide generation may be related with the suppression of LTD in striatum. Suppression of free radical generation from different sources in the neuron may help to develop new therapeutical approaches and can prevent neurodegeneration in the striatum.