INVESTIGATIONS ON THE INFLUENCE OF L-DOPA ON EXPERIMENTAL EPILEPSY

Investigations were carried out on the influence of L-Dopa on experimental epilepsy. L-Dopa was found to be able to markedly antagonize electroshock seizures in mice and audiogenic seizures (AGS) in rats. These effects of L-Dopa are mainly related to an increase of the concentration of dopamine (DA)in the whole brain of animals: 1). The antiaudiogenic seizure effects of L-Dopa was shown to be parallel with the incerase of the whole brain DA content, 2). Apomorphin, an agonist of dopaminergic receptor (DAR), also antagonized AGS in rats, Droperidol, an antagonist of DAR, in contrast, markedly reduced the anticonvulsant effect of L-Dopa, 3). The combined treatment with L-Dopa and disulfiram markedly reduced the whole brain NE content by 38% and signficantly increased the DA content. The anti-convulsant effects of L-Dopa was not altered. Treatment with disulfiram alone also markedly antagonized the AGS in rats(P<0.01),4). An intracerebroventricular injection of dihydroxyphenylserine (Dops) to rats, increased the whole brain NE content by 42%, the DA content, however, did not undergo any change. The susceptibility to AGS was not affected. All these results indicate that DA is more important than NE in the modulation of AGS.