title: Prostanoid receptor expression by human airway smooth muscle cells and regulation of the secretion of granulocyte colony-stimulating factor.
abstract: The prostanoid receptors on human airway smooth muscle cells (HASMC) that augment the release by IL-1beta of granulocyte colony-stimulating factor (G-CSF) have been characterized and the signaling pathway elucidated. PCR of HASM cDNA identified products corresponding to EP(2), EP(3), and EP(4) receptor subtypes. These findings were corroborated at the protein level by immunocytochemistry. IL-1beta promoted the elaboration of G-CSF, which was augmented by PGE(2). Cicaprost (IP receptor agonist) was approximately equiactive with PGE(2), whereas PGD(2), PGF(2alpha), and U-46619 (TP receptor agonist) were over 10-fold less potent. Neither SQ 29,548 nor BW A868C (TP and DP(1) receptor antagonists, respectively) attenuated the enhancement of G-CSF release evoking any of the prostanoids studied. With respect to PGE(2), the EP receptor agonists 16,16-dimethyl PGE(2) (nonselective), misoprostol (EP(2)/EP(3) selective), 17-phenyl-omega-trinor PGE(2) (EP(1) selective), ONO-AE1-259, and butaprost (both EP(2) selective) were full agonists at enhancing G-CSF release. AH 6809 (10 microM) and L-161,982 (2 microM), which can be used in HASMC as selective EP(2) and EP(4) receptor antagonists, respectively, failed to displace to the right the PGE(2) concentration-response curve that described the augmented G-CSF release. In contrast, AH 6809 and L-161,982 in combination competitively antagonized PGE(2)-induced G-CSF release. Augmentation of G-CSF release by PGE(2) was mimicked by 8-BrcAMP and abolished in cells infected with an adenovirus vector encoding an inhibitor protein of cAMP-dependent protein kinase (PKA). These data demonstrate that PGE(2) facilitates G-CSF secretion from HASMC through a PKA-dependent mechanism by acting through EP(2) and EP(4) prostanoid receptors and that effective antagonism is realized only when both subtypes are blocked concurrently.
authors.affiliation: Thoraic Medicine, National Heart and Lung Institute, Imperial College London, London, UK.
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Clarke
authors.forename: Maria G
authors.initials: MG
authors.lastname: Belvisi
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Smith
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hardaker
authors.forename: Magdi H
authors.initials: MH
authors.lastname: Yacoub
authors.forename: Koremu K
authors.initials: KK
authors.lastname: Meja
authors.forename: Robert
authors.initials: R
authors.lastname: Newton
authors.forename: Donna M
authors.initials: DM
authors.lastname: Slater
authors.forename: Mark A
authors.initials: MA
authors.lastname: Giembycz
mesh_terms: D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology; D015232:Dinoprostone / Q000502:physiology; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D018078:Receptors, Prostaglandin E / Q000502:physiology*; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D014132:Trachea / Q000166:cytology / Q000378:metabolism*
chemical_list: C545644:PTGER2 protein, human; C545650:PTGER4 protein, human; D018078:Receptors, Prostaglandin E; D058307:Receptors, Prostaglandin E, EP2 Subtype; D058309:Receptors, Prostaglandin E, EP4 Subtype; D016179:Granulocyte Colony-Stimulating Factor; D017868:Cyclic AMP-Dependent Protein Kinases; D015232:Dinoprostone