Presence of NK1 receptors on a mucosal-like mast cell line, RBL-2H3 cells.
Reverse transcription--polymerase chain reaction of mRNA from rat RBL-2H3 cells yielded a 316 base pair band consistent with that predicted for the neurokinin-1 (NK1) receptor. Saturation and competition binding with 125I-labeled Bolton-Hunter substance P, substance P fragments, and a series of selective tachykinin receptor agonists and antagonists demonstrated that RBL-2H3 cells express high affinity binding sites for substance P on their surfaces with the kinetic and pharmacological properties of NK1 receptors. The pharmacology of these 125I-labeled substance P binding sites was (from most to least potent) [Sar9,Met(O2)11]substance P > substance P 4-11 >> GR82334 << MEN 10,376. However, substance P 1-4, substance P 8-11, substance P 9-11, and [Trp7, beta-Ala8]neurokinin A 4-10 failed to compete for binding. The metabolically stable NK1 receptor agonist, [Sar9,Met(O2)11] substance P, caused a 49% increase in 5-hydroxytryptamine release above basal levels. The results demonstrate the presence of functional NK1 receptors on RBL-2H3 cells, a mucosal-like mast cell line.
Cooke
H J
HJ
Department of Pharmacology, Ohio State University, Columbus 43210, USA. cooke.l@osu.edu
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Alferes
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Wolfe
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D000818:Animals; D001667:Binding, Competitive; D002478:Cells, Cultured / Q000187:drug effects; D008407:Mast Cells / Q000378:metabolism*; D015288:Neurokinin A / Q000031:analogs & derivatives / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D051381:Rats; D018040:Receptors, Neurokinin-1 / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D013373:Substance P / Q000378:metabolism* / Q000494:pharmacology
D010446:Peptide Fragments; D018040:Receptors, Neurokinin-1; C069192:neurokinin A(4-10), Tyr(5)-Trp(6,8,9)-Lys(10)-; D013373:Substance P; D015288:Neurokinin A