The role of GABAergic receptors in acute, subacute, and withdrawal syndrome on pain and seizure thresholds in mice: A connection to mitochondrial function and oxidative stress in the brain.

One of the most serious neurological disorders is epilepsy. This study aimed to investigate the effects of baclofen, a GABA receptor agonist, on pain and seizure thresholds, as well as on oxidative damage in brain mitochondrial membranes of mice. Sixty male mice were divided into 10 groups. Control, baclofen (1, 5, and 10 mg/kg) with short-term exposure (1 day), long-term exposure (7 days), and withdrawal syndrome (eight days). The withdrawal syndrome was evaluated one day after the last dose of the drug. Hotplate and tail-flick tests were performed to assess pain threshold, and the rotarod was used to assess motor coordination. The seizure threshold and oxidative stress markers, including reactive oxygen species (ROS), malondialdehyde (MDA), protein carbonyl (PC), glutathione (GSH), and the MTT assay, were investigated. The results showed that baclofen (10 mg/kg) in short-term and all doses (1, 5, and 10 mg/kg) in long-term increased the seizure threshold. Evaluation of motor function and coordination in mice revealed decreased motor activity. The effect of baclofen on oxidative damage showed that, in long-term exposure, it improved mitochondrial ROS, malondialdehyde, and GSH levels. Protein carbonyl and MTT tests did not show a significant difference. A GABAB receptor agonist causes a dose- and time-dependent increase in the seizure threshold. Baclofen could reduce oxidative damage by decreasing ROS levels and malondialdehyde formation, and increasing GSH content.