FFA2 allosteric agonist. Inhibits forskolin-induced cAMP increase and stimulates 35SGTPγS binding in biochemical assays (pEC50 values are 6.9 and 7.23, respectively). Binds at allosteric binding site. In functional assays, displays positive allosteric modulation of FFA-induced Gi signaling and negative allosteric modulation of FFA-induced Gq/G11 signaling. Inhibits lipolytic effect of isoproterenol (pEC50 = 5.03) and induces migration of human neutrophils in vitro. Bolognini et al (2016) A novel allosteric activator of free fatty acid 2 receptor displays unique Gi-functional bias. J.Biol.Chem. 291 18915 PMID:27385588 |Sergeev et al (2017) A single extracellular amino acid in free fatty acid receptor 2 defines antagonist species selectivity and G protein selection bias. Sci.Rep. 7 13741 PMID:29061999
Isoproterenol-d7 is intended for use as an internal standard for the quantification of isoproterenol by GC- or LC-MS. Isoproterenol is an agonist of β1- and β2-adrenergic receptors (β1- and β2-ARs; Kis = 224 and 458 nM, respectively). It is selective for β1- and β2-ARs over β3-ARs (Ki = 1,570 nM). Isoproterenol inhibits contractions in isolated field-stimulated rat vas deferens (EC50 = 45.6 nM). In vivo, isoproterenol (0.33 mg kg) decreases blood pressure and increases water intake in nephrectomized rats. It reduces blood pressure and increases heart rate in renal hypertensive rabbits. Isoproterenol inhibits histamine-induced bronchospasms in anesthetized dogs. Formulations containing isoproterenol have been used in the treatment of bradydysrhythmias and to improve breathing during anesthesia.
Fenspiride-d5 is intended for use as an internal standard for the quantification of fenspiride by GC- or LC-MS. Fenspiride is an antagonist of histamine H1 receptors and a non-steroidal anti-inflammatory drug (NSAID). It inhibits histamine-induced contraction of isolated guinea pig trachea but not histamine-induced inotropy of isolated guinea pig heart. It also inhibits phosphodiesterase 4 (PDE4), PDE5, and PDE3 (IC50s = 69, ~158, and 363 µM, respectively, in isolated human bronchi derived from patients with lung cancer). It is selective for these phosphodiesterases over PDE1 and PDE2, where it provides less than 25% inhibition. Fenspiride potentiates the airway relaxant effects of isoproterenol and sodium nitroprusside indicating an effect on cAMP and cGMP phosphodiesterases, respectively. Aerosolized fenspiride (1 mg ml) reverses bronchoconstriction induced by capsaicin and, when used at aerosolized concentrations ranging from 1-10 mg ml, reduces cough induced by citric aci......