title: Expression of functional delta opioid receptors in vascular smooth muscle.
abstract: We evaluated smooth muscle from human internal mammary artery and rat aorta for the presence of delta opioid receptors. Radioligand receptor competition studies using the delta-receptor selective agonist, [3H]-[D-Ala2, Met5] enkephalinamide (DAMA) suggested the expression of a high affinity binding site in rat and human blood vessels that was consistent with the delta-2 opioid receptor subtype. Using RT-PCR with primers to the cloned delta opioid receptor (DOR), a cDNA fragment identical to the known DOR sequence was obtained from the smooth muscle cell line, A-10. Stimulation of A-10 cells with DAMA resulted in a significant mobilization of intracellular calcium and membrane depolarization. Exposure of aortic rings denuded of endothelium to DAMA induced a naltrindole-senstive increase in contractile tone. These data demonstrate the presence of a functional DOR in vascular smooth muscle and a direct impact of opioids on vascular contractile tone.
authors.affiliation: Queens College and Graduate School of the City University of New York, Flushing, NY 11367, USA.
authors.forename: R W
authors.initials: RW
authors.lastname: Saeed
authors.forename: G B
authors.initials: GB
authors.lastname: Stefano
authors.forename: J D
authors.initials: JD
authors.lastname: Murga
authors.forename: T W
authors.initials: TW
authors.lastname: Short
authors.forename: F
authors.initials: F
authors.lastname: Qi
authors.forename: T V
authors.initials: TV
authors.lastname: Bilfinger
authors.forename: H I
authors.initials: HI
authors.lastname: Magazine
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D001667:Binding, Competitive / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D020881:Enkephalin, D-Penicillamine (2,5)- / Q000378:metabolism / Q000494:pharmacology; D016308:Enkephalin, Leucine-2-Alanine / Q000378:metabolism / Q000494:pharmacology; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D015870:Gene Expression; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009271:Naltrexone / Q000031:analogs & derivatives* / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017465:Receptors, Opioid, delta / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D012333:RNA, Messenger; D017465:Receptors, Opioid, delta; D004744:Enkephalin, Methionine; D009271:Naltrexone; C022118:enkephalinamide-Met, Ala(2)-; D016308:Enkephalin, Leucine-2-Alanine; D020881:Enkephalin, D-Penicillamine (2,5)-; C055382:naltrindole; D002118:Calcium