Abstract |
Isolated endothelium-denuded segments of the human internal thoracic artery (ITA) and saphenous vein (SV) have been used for characterization of vasoinhibitory effects of the chromostatin (hChs) sequence of human chromogranin A (CGA124-143). In SV preincubation with hChs inhibited the response to depolarizing high K+ in Ca(2+)-free medium in a concentration dependent manner (EC50 approximately 2 nM). At 200 nM hChs the tension response to high K+ (80 mM) was inhibited by 44% (n = 8) and the tension response to noradrenaline (2.6 microM) was inhibited by 20% (n = 6), but the tension response to endothelin-1 (65 nM) (ET-1) was not affected. In ITA no effect of hChs was observed on tension response to K+ or ET-1 in Ca(2+)-free medium. On the other hand, in Ca(2+)-containing medium the tension evoked by 65 nM ET-1 was no longer sustained in segments preincubated with 200 nM hChs and declined spontaneously to 76 +/- 12% (n = 6) of maximal tension after 6 min. A vascular function for the Chs sequence of the human CGA is thus indicated, inhibiting different components of vasoconstrictor responses in the human SV and ITA segments.
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Authors | S Aardal, E Galindo, D Aunis, K B Helle |
Journal | Regulatory peptides
(Regul Pept)
Vol. 47
Issue 1
Pg. 25-32
(Aug 13 1993)
ISSN: 0167-0115 [Print] Netherlands |
PMID | 8210519
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Chromogranin A
- Chromogranins
- Endothelins
- Peptide Fragments
- chromostatin
- Calcium
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Topics |
- Calcium
(metabolism)
- Chromogranin A
- Chromogranins
(physiology)
- Endothelins
(antagonists & inhibitors)
- Endothelium, Vascular
(physiology)
- Humans
- In Vitro Techniques
- Muscle Contraction
(physiology)
- Muscle, Smooth, Vascular
(physiology)
- Peptide Fragments
(physiology)
- Saphenous Vein
- Thoracic Arteries
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