title: Sex steroids effects on guinea pig airway smooth muscle tone and intracellular Ca2+basal levels.
abstract: Testosterone (TES), other androgens and female sex steroids induce non-genomic rapid relaxing effects in airway smooth muscle (ASM). In guinea pig ASM, basal tension was relaxed by dehydroepiandrosterone (DHEA) and TES; 17β-estradiol (E2) had a small effect. Blockers of L-type voltage dependent Ca2+channel (L-VDCC, D-600) and store operated Ca2+channel (SOC, 2-APB) also relaxed the basal tone. In tracheal myocytes, DHEA and TES diminished intracellular basal Ca2+concentrations (b[Ca2+]i) as D-600+2-APB but to a higher extend. TES after D-600+2APB or Pyr3, a blocker of canonical transient receptor potential 3 (TRPC3), further decreasedb[Ca2+]irendering this response equal to TES alone. With indomethacin, theb[Ca2+]idecrease induced by the blockade of L-VDCC and TRPC3 was not changed by the addition of TES. PGE2or forskolin addition after D600+2-APB, decreasedb[Ca2+]iresembling TES response. An adenylate cyclase inhibitor followed by D-600+2-APB loweredb[Ca2+]i, TES showed no further effect. Carbachol-induced [Ca2+]i increment was reduced by TES or DHEA. 17β-estradiol diminished KCl-induced contraction and, in tracheal myocytes, the voltage-dependent inward Ca2+current.
  
  
  
  DHEA and TES diminish ASM tone andb[Ca2+]i by blocking L-VDCC and probably a constitutively active TRPC3, and by PGE2synthesis. E2 lowers ASM basal tone by blocking only L-VDCC.
authors.affiliation: Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico.
authors.forename: Edgar
authors.initials: E
authors.lastname: Flores-Soto
authors.affiliation: Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico.
authors.forename: Jorge
authors.initials: J
authors.lastname: Reyes-García
authors.affiliation: Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico.
authors.forename: Abril
authors.initials: A
authors.lastname: Carbajal-García
authors.affiliation: Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico.
authors.forename: Elías
authors.initials: E
authors.lastname: Campuzano-González
authors.affiliation: Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Perusquía
authors.affiliation: Departamento de Investigación en Hiperreactividad Bronquial, Instituto Nacional de Enfermedades Respiratorias, 14080, Ciudad de México, Mexico.
authors.forename: Bettina
authors.initials: B
authors.lastname: Sommer
authors.affiliation: Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico. Electronic address: lmmr@unam.mx.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Montaño
mesh_terms: D000818:Animals; D001896:Boron Compounds / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D020746:Calcium Channels, L-Type / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D003687:Dehydroepiandrosterone / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D005711:Gallopamil / Q000494:pharmacology; D012739:Gonadal Steroid Hormones / Q000494:pharmacology*; D006168:Guinea Pigs; D042541:Intracellular Space / Q000378:metabolism*; D008297:Male; D032342:Muscle Cells / Q000187:drug effects / Q000378:metabolism; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology*; D011453:Prostaglandins / Q000378:metabolism; D050052:TRPC Cation Channels / Q000378:metabolism; D013739:Testosterone / Q000494:pharmacology; D014132:Trachea / Q000502:physiology*
chemical_list: D001896:Boron Compounds; D020746:Calcium Channels, L-Type; D012739:Gonadal Steroid Hormones; D011453:Prostaglandins; D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; D005711:Gallopamil; D013739:Testosterone; D003687:Dehydroepiandrosterone; D004958:Estradiol; D002217:Carbachol; D000242:Cyclic AMP; C109986:2-aminoethoxydiphenyl borate; D002118:Calcium
keywords: 17β-estradiol; Canonical transient receptor potential 3 channel; Dehydroepiandrosterone; L-type Ca(2+) channels; Store operated Ca(2+) channels; Testosterone