An FP prostaglandin (PG) receptor on the A7r5 rat aorta smooth muscle cell line has been characterized by assays of phosphoinositide (PI) turnover and intracellular calcium mobilization stimulated by structurally diverse PGs. In the PI turnover assay, cloprostenol was the most potent PG tested, with a potency (EC50) of 0.84 +/- 0.06 nM (mean +/- S.E.M., n = 34), and was a full agonist. Other known FP receptor agonists tested in this assay had efficacies > or = 85% of the cloprostenol value and high potencies: 16-phenoxy PGF2 alpha (2.05 +/- 0.19 nM), 17-phenyl PGF2 alpha (2.80 +/- 0.59 nM), fluprostenol (4.45 +/- 0.19 nM), PGF2 alpha (30.9 +/- 2.82 nM) and PhXA85 (43.5 +/- 11.4 nM). Other classes of PGs evaluated (PGD2, enprostil, 17-phenyl PGE2, PGE2, sulprostone and U-46619) were less potent and less efficacious than the FP receptor agonists, or were inactive. For a large group of standard PGs evaluated in the PI turnover assay, both potencies and efficacies correlated well with those reported for the FP receptor of Swiss mouse 3T3 fibroblasts. The potencies of fluprostenol and PGF2 alpha as stimuli of intracellular calcium mobilization matched well their potencies in the PI turnover assay, but fluprostenol had twice the efficacy of PGF2 alpha. Both signaling responses stimulated by fluprostenol were significantly inhibited by U73122, a selective inhibitor of phosphoinositide turnover (IC50 = 1.25 +/- 0.16 microM for PI turnover), and by chelation of calcium in the medium. Together with the PI turnover data, these studies of intracellular calcium mobilization linked to activation of the FP receptor, provide additional characterization of the pharmacological properties of this receptor.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCamphor binding of Pseudomonas putida cytochrome P-450. Kinetics and thermodynamics of the reactionBrenda Walker Griffin and Julian A. PetersonCite this: Biochemistry 1972, 11, 25, 4740–4746Publication Date (Print):December 1, 1972Publication History Published online1 May 2002Published inissue 1 December 1972https://pubs.acs.org/doi/10.1021/bi00775a017https://doi.org/10.1021/bi00775a017research-articleACS PublicationsRequest reuse permissionsArticle Views339Altmetric-Citations131LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts