Abstract |
Epithelioid cells in the chicken thoracic aorta are shown to contain 5-hydroxytryptamine (5-HT) in immunocytochemical studies. To determine whether these cells act as chemoreceptors, as do type I cells of the carotid body, we examined the effects of hypoxia and acidosis on the release of 5-HT from the chicken thoracic aorta. Hypoxia caused the output of 5-HT in incubation medium. A reduction of pH to 6.8 failed to evoke 5-HT release. The response to hypoxia was inhibited by the removal of extracellular Ca2+ and by nifedipine and omega-conotoxin GVIA. These results suggest that epithelioid cells in the chicken thoracic aorta are chemoreceptors which sense a decrease in PO2 and then release 5-HT by Ca2+ influx through voltage-dependent L- and N-type Ca2+ channels. The epithelioid cells in the chicken aorta may be a useful model for pharmacological and physiological studies of 5-HT-containing cells.
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Authors | S Ito, T Ohta, Y Nakazato |
Journal | British journal of pharmacology
(Br J Pharmacol)
Vol. 122
Issue 5
Pg. 799-801
(Nov 1997)
ISSN: 0007-1188 [Print] England |
PMID | 9384492
(Publication Type: Journal Article)
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Chemical References |
- Calcium Channel Blockers
- Peptides
- Serotonin
- omega-Conotoxin GVIA
- Nifedipine
- Calcium
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Topics |
- Animals
- Aorta, Thoracic
(cytology, drug effects)
- Calcium
(metabolism)
- Calcium Channel Blockers
(pharmacology)
- Cell Hypoxia
- Chemoreceptor Cells
(drug effects, metabolism)
- Chickens
- Chromatography, High Pressure Liquid
- Epithelioid Cells
(drug effects, metabolism)
- Hydrogen-Ion Concentration
- In Vitro Techniques
- Male
- Nifedipine
(pharmacology)
- Peptides
(pharmacology)
- Serotonin
(metabolism)
- omega-Conotoxin GVIA
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