Somatostatin regulates intracellular signaling in human carotid endothelial cells.
Somatostatin (somatotropin release inhibitory factor; SRIF) is an endogenous peptide produced at sites of inflammation, making the SRIF a candidate in regulating vascular inflammation. We have used primary human coronary artery endothelial cells (hCAEC) as a model to study SRIF's vascular actions. RT-PCR analysis of hCAEC total mRNA demonstrated the presence of the sst(4) receptor subtype, providing a target for SRIF intracellular signaling. Western blotting with phospho-specific ERK1/2 antibodies showed that SRIF-14 acutely inhibited basal phosphorylation of the extracellular regulated kinases (ERK1/2) by 80%. In addition, SRIF-14 treated hCAEC cell lysates showed a 2.6-fold increase in phosphatase activity, which was inhibited by sodium vanadate. Furthermore, SRIF-14 appeared to be anti-inflammatory in hCAEC as IL-1beta-induced adhesion molecule expression was reduced by 50%. Together, these results show that the coronary artery endothelium is a direct target of SRIF action.
Badway
Amy C
AC
Department of Biology, Seton Hall University, South Orange, NJ 07079, USA.
West
Frances Mae
FM
Tente
Susana M
SM
Blake
Allan D
AD
D002339:Carotid Arteries / Q000033:anatomy & histology*; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology*; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D007375:Interleukin-1 / Q000378:metabolism; D008565:Membrane Proteins; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010766:Phosphorylation; D020033:Protein Isoforms / Q000378:metabolism; D017481:Receptors, Somatostatin / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D013004:Somatostatin / Q000378:metabolism*; D014638:Vanadates / Q000378:metabolism; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
D007375:Interleukin-1; D008565:Membrane Proteins; D020033:Protein Isoforms; D017481:Receptors, Somatostatin; D019010:Vascular Cell Adhesion Molecule-1; C098681:somatostatin receptor subtype-4; D018799:Intercellular Adhesion Molecule-1; D014638:Vanadates; D013004:Somatostatin; D020928:Mitogen-Activated Protein Kinases