Proconvulsive effects of the mitochondrial respiratory chain inhibitor - 3-nitropropionic acid

The role of impaired mitochondrial function in processes leading to the generation of seizures was studied in mice. An inhibitor of mitochondrial complex III, 3-nitropropionic acid, which is known to evoke convulsions per se, and was used here in subthreshold dose, enhanced seizures generated by electric current and application of 4-aminopyridine. In contrast, 3-nitropropionic acid did not affect convulsions induced by gamma-aminobutyric acid (GABA) receptor antagonists - bicuculline, pentylenetetrazol and picrotoxin, glycine antagonist - strychnine, cholinomimetic drug-pilocarpine, and kynurenine aminotransferase inhibitor - aminooxyacetic acid. It is hypothesised that deranged mitochondrial metabolism renders the central nervous system more susceptible to factors inducing seizures via direct depolarization. (C) 2000 Elsevier Science B.V. All rights reserved.