Are the central dopaminergic synapses related to the convulsive-seizure threshold?--Effects of central dopaminergic drugs on the picrotoxin convulsive-seizure threshold. Interaction with diazepam, meta-tolylcarbamide and theophylline
Markovska, V.L.; Georgiev, V.P.
Acta Physiologica et Pharmacologica Bulgarica 2(4): 59-65
1976
ISSN/ISBN: 0323-9950 PMID: 1029380 Document Number: 107193
The effect of agents stimulating (apomorphine) and blocking (pimozide) dopaminergic receptors and their interactions with the central neurodepressants (diazepam and metatolylcarbamide (MTC)), and the phosphodiesterase inhibitor theophylline on the picrotoxin convulsive-seizure threshold (PCST) upon timed i.v. infusion were studied in male albino mice. Apomorphine (2 and 5 mg/kg) had a markedly increasing effect on PCST. Pimozide (1 and 10 mg/kg) substantially lowered PCST. Diazepam (10 mg/kg) increased PCST, while MTC (50 mg/kg) showed a tendency towards increase. Theophylline (10 mg/kg) lowered PCST. In combined application apomorphine (2 mg/kg) potentiated the rise in PCST induced by diazepam and MTC. Pimozide (1 mg/kg) moderately intensified the effects of diazepam and MTC. Theophylline potentiated the effects of pimozide (1 mg/kg) and diazepam on PCST. Dopaminergic synapses probably have predominantly inhibitory effects in the CNS, and are associated with cyclic nucleotides. They play a modulating role in maintaining a definite excitability threshold in the CNS and are associated with the picrotoxin convulsive-seizure threshold.