RESUMO
The correlation between pentylenetetrazole [PTZ]-induced kindling and the cortical nitric oxide synthase [NOS], intracellular calcium [Ca2+]i, glutamate and free radicals was studied in mice as well as the modulatory action of nifedipine and taurine on these parameters. Male Swiss albino mice were used and divided into three groups. All the kindled groups were sacrificed 24 hours after the last injection. Compared with the normal control group, PTZ- kindled mice had significantly higher levels of [Ca2+]i, malondialdehyde [MDA], NOS and lactate dehydrogenase [LDH], but had lower levels of superoxide dismutase [SOD] and reduced glutathione [GSH]. Acute seizures of the same intensity did not induce these alterations indicating their relation to the kindling phenomenon and not to seizure activity. The effect of taurine, known as an antioxidant, was more pronounced than that of the Ca2+ channel blocker, nifedipine. The first drug reverted the PTZ- kindled action on [Ca2+]i, NOS, LDH, GSH and SOD; while, nifedipine restored only LDH and GSH levels. However, both drugs did not restore the elevated MDA level