Abstract
Caveolae are plasmamembrane regions which take part in the regulation of intracellular trafficking and signaling of tyrosine kinase receptors. Insulin and IGF-I receptors and their intracellular substrates localize in caveolae. Also eNOS is targeted to caveolae and caveolin-1, the major caveolar protein, acts as a regulator of eNOS activity. Since Insulin and IGF-I phosphorylate and activate eNOS, we investigated the role of caveolin-1 in Insulin and IGF-I stimulated eNOS activity. Here we show that: (1) in human endothelial cells, Insulin and IGF-I stimulate eNOS phosphorylation in a different manner both qualitatively and quantitatively; (2) caveolin-1 down regulation abolishes Insulin and IGF-I stimulated eNOS phosphorylation. These results suggest that caveolae could represent an intracellular site that contributes to differentiate IR and IGF-IR activity, and demonstrate the role of caveolin-1 in the eNOS activation by Insulin and IGF-I.
Original language | English |
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Pages (from-to) | 849-852 |
Number of pages | 4 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 337 |
Issue number | 3 |
DOIs | |
Publication status | Published - Nov 25 2005 |
Keywords
- Caveolin-1
- eNOS
- HUVECs
- IGF-I receptor
- Insulin receptor
ASJC Scopus subject areas
- Biochemistry
- Biophysics
- Molecular Biology