hb-7 and Epilepsy

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)

Topics: Allylglycine; Animals; Anticonvulsants; Cats; Electroencephalography; Epilepsy; Pentobarbital; Photic Stimulation; Synaptic Transmission

The effects of barbiturate HB-7 (2-hydroxylamine-5-ethyl-5-sec-pentylbarbituric acid) injected intraperitoneally compared to the effects of pentobarbital and/or phenobarbital were investigated in three series of experiments on cats: normal electrocorticogram (ECoG); pentylentetrazol-induced generalized paroxysmal ECoG; and paroxysmal ECoG activity induced by topical application of penicillin on the exposed cortical surface. In the first series, HB-7 led to the appearance of ECoG spindles of the same type as those elicited by pentobarbital. In the second series (pentylentetrazol-treated group), HB-7 increased the two thresholds: one associated with the appearance of isolated paroxysmal spike-wave complexes and the other corresponding to the appearance of generalized paroxysmal ECoG activity. In the third series, HB-7 led to an inhibition of penicillin spikes, both in the focus itself and in the other cortical areas where they propagated. The possibility for using HB-7 as an antiepileptic drug was discussed.

Topics: Animals; Anticonvulsants; Cats; Electroencephalography; Epilepsy; Penicillins; Pentobarbital