Abstract | OBJECTIVE: Vascular hyporesponsiveness is a major complication following severe trauma and shock. It plays important roles in the development of shock and seriously interferes with the treatment of shock. The mechanism responsible for the occurrence of vascular hyporesponsiveness has not been fully understood. The purpose of this study was to determine whether the alpha subunit tyrosine sites of large conductance calcium-activated potassium channel (BK(Ca)) could be phosphorylated and whether the phosphorylation of BK(Ca) was closely associated with the activation of BK(Ca) and the development of vascular hyporesponsiveness following hemorrhagic shock in rats. METHODS: A hemorrhagic shock (30 mm Hg for 0.5, 2, 4 h) model of Wistar rats was established. Phosphorylation of tyrosine residues of the BK(Ca) alpha subunit from vascular smooth muscle cells (VSMC) in superior mesenteric arteries (SMA) was detected by immunoprecipitation and Western blotting. BK(Ca) activity was evaluated by cell-attached patch clamping. The vascular responsiveness of SMA to norepinephrine was measured with an isolated organ perfusion system. RESULTS: CONCLUSION: The tyrosine residues of BK(Ca) alpha subunit of SMA were phosphorylated following hemorrhagic shock, which was regulated by PTK and PTP and appeared to be related to the activation of BK(Ca) and the development of vascular hyporesponsiveness following hemorrhagic shock.
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Authors | Rong Zhou, Liangming Liu, Deyao Hu |
Journal | Cardiovascular research
(Cardiovasc Res)
Vol. 68
Issue 2
Pg. 327-35
(Nov 01 2005)
ISSN: 0008-6363 [Print] England |
PMID | 16043163
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Kcnma1 protein, rat
- Large-Conductance Calcium-Activated Potassium Channel alpha Subunits
- Potassium Channels
- Quaternary Ammonium Compounds
- Vanadates
- Tyrosine
- tetrabutylammonium
- Genistein
- Protein-Tyrosine Kinases
- Protein Tyrosine Phosphatases
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Topics |
- Animals
- Genistein
(pharmacology)
- Hypotension
(metabolism)
- Large-Conductance Calcium-Activated Potassium Channel alpha Subunits
- Mesenteric Artery, Superior
- Muscle, Smooth, Vascular
(drug effects, metabolism)
- Phosphorylation
- Potassium Channels
(metabolism)
- Protein Tyrosine Phosphatases
(antagonists & inhibitors)
- Protein-Tyrosine Kinases
(antagonists & inhibitors)
- Quaternary Ammonium Compounds
(pharmacology)
- Rats
- Rats, Wistar
- Shock, Hemorrhagic
(metabolism)
- Time Factors
- Tyrosine
(metabolism)
- Vanadates
(pharmacology)
- Vascular Resistance
(drug effects)
- Vasodilation
(drug effects)
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