title: Hydrogen sulfide and hypoxia-induced changes in TASK (K2P3/9) activity and intracellular Ca(2+) concentration in rat carotid body glomus cells.
abstract: Acute hypoxia depolarizes carotid body chemoreceptor (glomus) cells and elevates intracellular Ca(2+) concentration ([Ca(2+)]i). Recent studies suggest that hydrogen sulfide (H2S) may serve as an oxygen sensor/signal in the carotid body during acute hypoxia. To further test such a role for H2S, we studied the effects of H2S on the activity of TASK channel and [Ca(2+)]i, which are considered important for mediating the glomus cell response to hypoxia. Like hypoxia, NaHS (a H2S donor) inhibited TASK activity and elevated [Ca(2+)]i. To inhibit the production of H2S, glomus cells were incubated (3h) with inhibitors of cystathionine-β-synthase and cystathionine-γ-lyase (DL-propargylglycine, aminooxyacetic acid, β-cyano-L-alanine; 0.3 mM). SF7 fluorescence was used to assess the level of H2S production. The inhibitors blocked L-cysteine- and hypoxia-induced elevation of SF7 fluorescence intensity. In cells treated with the inhibitors, hypoxia produced an inhibition of TASK activity and a rise in [Ca(2+)]i, similar in magnitude to those observed in control cells. L-cysteine produced no effect on TASK activity or [Ca(2+)]i and did not affect hypoxia-induced inhibition of TASK and elevation of [Ca(2+)]i. These findings suggest that under normal conditions, H2S is not a major signal in hypoxia-induced modulation of TASK channels and [Ca(2+)]i in isolated glomus cells.
authors.affiliation: Department of Physiology and Biophysics, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, United States. Electronic address: Donghee.kim@rosalindfranklin.edu.
authors.forename: Donghee
authors.initials: D
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, 13 Children's Way, Little Rock, AR 72202, United States.
authors.forename: Insook
authors.initials: I
authors.lastname: Kim
authors.affiliation: Department of Physiology and Biophysics, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, United States.
authors.forename: Jiaju
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Physiology and Biophysics, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, United States.
authors.forename: Carl
authors.initials: C
authors.lastname: White
authors.affiliation: Department of Pediatrics, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, 13 Children's Way, Little Rock, AR 72202, United States. Electronic address: carrolljohnl@uams.edu.
authors.forename: John L
authors.initials: JL
authors.lastname: Carroll
mesh_terms: D000480:Alkynes / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D002344:Carotid Body / Q000166:cytology*; D002628:Chemoreceptor Cells / Q000166:cytology / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D064426:Gasotransmitters / Q000494:pharmacology*; D005998:Glycine / Q000031:analogs & derivatives / Q000494:pharmacology; D006862:Hydrogen Sulfide / Q000494:pharmacology*; D000860:Hypoxia / Q000378:metabolism*; D007424:Intracellular Fluid / Q000187:drug effects; D008564:Membrane Potentials / Q000187:drug effects; D009419:Nerve Tissue Proteins; D018408:Patch-Clamp Techniques; D024683:Potassium Channels, Tandem Pore Domain / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017670:Sodium Compounds; D016559:Tacrolimus / Q000031:analogs & derivatives / Q000494:pharmacology; D013997:Time Factors
chemical_list: C112418:32-ascomycinyloxyacetic acid; D000480:Alkynes; D064426:Gasotransmitters; D009419:Nerve Tissue Proteins; D024683:Potassium Channels, Tandem Pore Domain; D017670:Sodium Compounds; C420132:potassium channel subfamily K member 3; C524957:sodium hydride; C009055:propargylglycine; D002118:Calcium; D005998:Glycine; D016559:Tacrolimus; D006862:Hydrogen Sulfide
keywords: Carotid body; Chemoreceptors; Hydrogen sulfide; Hypoxia; l-Cysteine