title: A new isoxazolic compound acts as alpha7 nicotinic receptor agonist in human umbilical vein endothelial cells.
abstract: Recent evidence suggests that the alpha7 nicotinic acetylcholine receptors (alpha7 nAChRs) participate in the development of angiogenesis and could be a new endothelial target for revascularization in therapeutic angiogenesis. It has been shown that in human umbilical vein endothelial cells (HUVECs) alpha7 nAChR agonists increase the intracellular calcium concentration ([Ca2+]i), thus inducing proliferation and vessel formation which are important stages of angiogenesis. In the present study we evaluated the effect of new isoxazole compounds on the cytosolic Ca2+ signal in HUVECs using the fluorescent Ca2+ indicator Fluo-3AM and probing the involvement of alpha7 nAChR by means of pharmacological tools. HUVECs expressed mainly alpha7 nAChR, since there was no significant difference in the increase in [Ca2+]i induced by nicotine, a non-selective nicotinic agonist, in relation to choline, a selective alpha7 nAChR agonist. The increase in [Ca2+]i induced by 1 mM choline was inhibited significantly (p = 0.014) in cells which had been pre-incubated for 15 min with methyllycaconitine (MLA), a selective alpha7 nAChR antagonist. The studied compounds 1, 2, and 3 induced an increase in [Ca2+]i in a dose-dependent manner. Compound 1 at 10 microM induced a greater increase in [Ca2+]i than compounds 2 and 3. The increase in [Ca2+]i induced by compound 1 was significantly inhibited by MLA (p = 0.013) and completely inhibited by mecamylamine, a non-selective nAChR antagonist, indicating that the isoxazolic compound 1 acts as an alpha7 nAChR agonist.
authors.forename: Magdalena P
authors.initials: MP
authors.lastname: Cortés
authors.forename: Rocío
authors.initials: R
authors.lastname: Alvarez
authors.forename: Evelyn
authors.initials: E
authors.lastname: Sepúlveda
authors.forename: Felipe
authors.initials: F
authors.lastname: Jiménez-Aspee
authors.forename: Luis
authors.initials: L
authors.lastname: Astudillo
authors.forename: Gabriel
authors.initials: G
authors.lastname: Vallejos
authors.forename: Margarita
authors.initials: M
authors.lastname: Gutiérrez
mesh_terms: D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D007555:Isoxazoles / Q000737:chemistry / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization; D014471:Umbilical Veins / Q000166:cytology / Q000187:drug effects*; D064569:alpha7 Nicotinic Acetylcholine Receptor / Q000819:agonists*
chemical_list: D007555:Isoxazoles; D064569:alpha7 Nicotinic Acetylcholine Receptor