5-HT7 receptor-mediated dilatation in the middle meningeal artery of anesthetized rats.

Abstract

Topical administration of 5-carboxamidotryptamine (5-CT; 0.01-1000 microM) to the exposed dura mater encephali of anesthetized rats produced decreases in blood pressure and dilatation in the middle meningeal artery. Pretreatment with the 5-HT(1B/1D) receptor antagonist, N-[4-methoxy-3-(4-methyl-1-piperazinyl) phenyl]-2'-methyl-4'-(5-methyl-1,2,4-oxadiazol-3-yl) [1,1-biphenyl]-4-carboxamide hydrochloride monohydrate (GR-127935; 1 mg/kg, i.v.), unmasked meningeal dilator responses to lower concentrations of 5-CT, and attenuated those to higher concentrations; GR-127935 also inhibited 5-CT-induced hypotension. The 5-HT7 receptor antagonist, (R)-1-{(3-hydroxyphenyl)sulfonyl}-2-{2-(2-(4-methyl-1-piperidinyl) ethyl} pyrrolidine (SB-269970; 1 mg/kg, i.v.), strongly inhibited dilator and hypotensive responses to 5-CT; the combination of GR-127935+SB-269970 (1 mg/kg, i.v., each) further inhibited meningeal and hypotensive responses. Thus, 5-CT may produce dilatation in the middle meningeal artery via 5-HT7 receptors; complex effects appear to involve 5-HT(1B/1D) receptors.

• Authors: José A Terrón, Esther Martínez-García
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 560 Issue 1 Pg. 56-60 (Mar 29 2007) ISSN: 0014-2999 [Print] Netherlands
• PMID: 17316605 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Receptors, Serotonin
• Serotonin Receptor Agonists
• serotonin 7 receptor
• Serotonin
• 5-carboxamidotryptamine

Topics

• Administration, Topical
• Animals
• Blood Pressure (drug effects)
• Dilatation
• Heart Rate (drug effects)
• Male
• Meningeal Arteries (drug effects, physiology)
• Meninges (blood supply, drug effects)
• Rats
• Rats, Wistar
• Receptors, Serotonin (drug effects, physiology)
• Serotonin (administration & dosage, analogs & derivatives, pharmacology)
• Serotonin Receptor Agonists (administration & dosage, pharmacology)