m-Trifluoromethyl-diphenyl diselenide attenuates pentylenetetrazole-induced seizures in mice by inhibiting GABA uptake in cerebral cortex slices

The present study investigated the anticonvulsive effect of the disubstituted diaryl diselenides diphenyl diselenide (PhSe)2, m-trifluoromethyl-diphenyl diselenide (m-CF3-C6H4Se)2, p-chloro-diphenyl diselenide (p-Cl-C6H4Se)2 and p-methoxyl-diphenyl diselenide (p-CH3O-C6H4Se)2 on a chemical model of seizure induced by pentylenetetrazol (PTZ) in mice. (PhSe)2, (p-Cl--C6H4Se)2 and (p-CH3O-C6H4Se)2 did not abolish seizures induced by PTZ in mice. (m-CF3-C6H4Se)2 at the dose of 100 mg/kg significantly prolonged the latency of the onset of the first convulsive episode and reduced the number of animals that presented seizures. To investigate the possible mechanisms involved in the anticonvulsant effect of (m-CF3-C6H4Se)2, mice were submitted to different associations (all drugs in a sub-effective dose); aminooxyacetic acid hemihydrochloride (AOAA, a -aminobutyric acid (GABA)-T inhibitor), diazepam (a GABAAreceptor agonist) or DL-2, 4-diamino-n-butyric acid hydrochloride (DABA, an inhibitor of GABA uptake) were pre-administered together with (m-CF3-C6H4Se)2.(m-CF3-C6H4Se)2 + DABA abolished seizures induced by PTZ in mice. (m-CF3-C6H4Se)2 administered alone or with PTZ decreased the levels of GABA uptake in cerebral cortex slices. The present study demonstrates that (m-CF3-C6H4Se)2 exerts anticonvulsant action by decreasing the levels of GABA uptake.