Bradykinin (BK) acutely increases endothelial nitric oxide (NO) production by activating endothelial NO synthase (eNOS), and this increase is in part correlated with enhanced phosphorylation/dephosphorylation of eNOS by several protein kinases and phosphatases. However, the signaling mechanisms producing this increase are still controversial. In an attempt to delineate the acute effect of BK on endothelial NO production, confluent bovine aortic endothelial cells were incubated with BK, and NO production was measured by NO-specific chemiluminescence. Significant increase in NO levels was detected as early as 1min after BK treatment, with concomitant increase in the phosphorylation of Ser1179 (bovine sequence) site of eNOS (eNOS-Ser1179). This acute effect of BK on both increases was blocked only by treatment of protein kinase A inhibitor H-89, but not by the inhibitors of calmodulin-dependent kinase II and protein kinase B, suggesting that the rapid increase in NO production by BK is mediated by the PKA-dependent phosphorylation of eNOS-Ser1179.
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - 11 Jul 2003|
Bibliographical noteFunding Information:
This work was supported in part by Korea National Institute of Health intramural research Grant (348-6111-213-000-207) and Science Research Center grant from Korea Science and Engineering Foundation (KOSEF) to the Nitric Oxide Radical Toxicology Research Center (NORTReC) to Dr. Inho Jo and by Biomedical Brain Research Center grant from Ministry of Health and Welfare to Dr. Sangmee Ahn Jo.
- Endothelial nitric oxide synthase
- Nitric oxide
- Protein kinase A