Anticonvulsive activity of a barbiturate derivative HB-7 in a model of allylglycine-induced epilepsy in cats.

With the aim of characterizing further the anticonvulsive activity of the newly-synthesized barbituric derivative 2-hydroxylamino-5-ethyl-5-sec. penthylbarbituric acid (HB-7), we studied its effects on allylglycine-induced epileptiform electrocorticogram (ECoG) in cats under acute conditions. Pentobarbital (PB) was used for comparison. Allylglycine (AG) was administered in a dose of 100 mg/kg i.v. to all cats. The control animals were treated with AG only. HB-7 and PB were applied in doses of 20 mg/kg i.p., about 60 min after AG. Intermittent light stimulation (ILS) at flash rate of 8/s and 25/s was applied to some animals. The ILS-stimulated animals were also divided in three groups: controls and animals treated with HB-7 or PB in the same dose. AG led to the appearance of paroxysmal ECoG activity: single and multiple spikes and spike-waves appeared first, to be followed later by generalized seizure activity. No AG-induced convulsions appeared in the cats treated with HB-7, but the AG-induced spikes and spike-waves remained unchanged. The effect of PB on the AG-induced paroxysmal ECoG activity was similar to that of HB-7, but the addition of PB provoked the appearance of slow waves and spindles, mixed with spikes and spike-waves. Although the paroxysmal character of the activity was more pronounced in the ILS-stimulated animals than in the group without ILS, HB-7 and PB (albeit to a lesser extent) inhibited the AG-induced discharges.(ABSTRACT TRUNCATED AT 250 WORDS)