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.
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Authors | Donghee Kim, Insook Kim, Jiaju Wang, Carl White, John L Carroll |
Journal | Respiratory physiology & neurobiology
(Respir Physiol Neurobiol)
Vol. 215
Pg. 30-8
(Aug 15 2015)
ISSN: 1878-1519 [Electronic] Netherlands |
PMID | 25956223
(Publication Type: Journal Article, Research Support, N.I.H., Extramural)
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Copyright | Copyright © 2015 Elsevier B.V. All rights reserved. |
Chemical References |
- 32-ascomycinyloxyacetic acid
- Alkynes
- Gasotransmitters
- Nerve Tissue Proteins
- Potassium Channels, Tandem Pore Domain
- Sodium Compounds
- potassium channel subfamily K member 3
- sodium hydride
- propargylglycine
- Calcium
- Glycine
- Tacrolimus
- Hydrogen Sulfide
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Topics |
- Alkynes
(pharmacology)
- Analysis of Variance
- Animals
- Animals, Newborn
- Calcium
(metabolism)
- Carotid Body
(cytology)
- Chemoreceptor Cells
(cytology, drug effects)
- Dose-Response Relationship, Drug
- Gasotransmitters
(pharmacology)
- Glycine
(analogs & derivatives, pharmacology)
- Hydrogen Sulfide
(pharmacology)
- Hypoxia
(metabolism)
- Intracellular Fluid
(drug effects)
- Membrane Potentials
(drug effects)
- Nerve Tissue Proteins
- Patch-Clamp Techniques
- Potassium Channels, Tandem Pore Domain
(metabolism)
- Rats
- Rats, Sprague-Dawley
- Sodium Compounds
- Tacrolimus
(analogs & derivatives, pharmacology)
- Time Factors
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