D-1 dopamine agonist administration reduces the threshold for convulsions produced by pilocarpine.

Abstract

Focal, limbic seizures were produced by systemically administered pilocarpine (200 mg/kg, i.p.); as previously described this dose produces limbic stereotypies but neither convulsions nor seizure-related brain damage. The pretreatment, 5 minutes prior pilocarpine, with the D-1 agonist SKF 38393 (-ED50 = 1 mg/kg; i.p.) induced convulsions similar to those produced by a higher, convulsant dose of pilocarpine. On the other hand, the pretreatment with the D-2 agonist LY 171555 failed to induce convulsions. The D-1 receptor antagonist SCH 23390 prevented the convulsions induced by SKF 38393 plus pilocarpine (200 mg/kg). This study indicates that D-1, but not D-2, receptor stimulation converts subconvulsant doses of pilocarpine into convulsant ones.

• Authors: P Barone, V Palma, S A Parashos, C Marin, T N Chase, G Campanella
• Journal: Bollettino della Societa italiana di biologia sperimentale (Boll Soc Ital Biol Sper) Vol. 65 Issue 4 Pg. 337-41 (Apr 1989) ISSN: 0037-8771 [Print] Italy
• PMID: 2570598 (Publication Type: Journal Article)

Chemical References

• Benzazepines
• Convulsants
• Dopamine Agents
• Ergolines
• Receptors, Dopamine
• Pilocarpine
• Quinpirole
• 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine

Topics

• 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine
• Animals
• Benzazepines (pharmacology)
• Convulsants (pharmacology)
• Dopamine Agents (pharmacology)
• Drug Synergism
• Ergolines (pharmacology)
• Male
• Pilocarpine (pharmacology, toxicity)
• Quinpirole
• Rats
• Rats, Inbred Strains
• Receptors, Dopamine (classification, drug effects)
• Seizures (chemically induced)