TY - JOUR
T1 - Possible roles of neuropeptide Y Y3-receptor subtype in rat aortic endothelial cell proliferation under hypoxia, and its specific signal transduction
AU - Chen, Zhi Yong
AU - Feng, Guo Gang
AU - Nishiwaki, Kimitoshi
AU - Shimada, Yasuhiro
AU - Fujiwara, Yoshihiro
AU - Komatsu, Toru
AU - Ishikawa, Naohisa
PY - 2007/8
Y1 - 2007/8
N2 - The present study was undertaken to determine whether neuropeptide Y (NPY) induces proliferation of rat aortic endothelial cells (RAECs). Since NPY increased the permeability of RAEC monolayers to large molecules via the NPY Y3 receptor, RAEC proliferation has been evaluated in terms of NPY-receptor subtypes and also intracellular mechanisms. RAECs were incubated with gases containing 20, 15, or 10% O2 and a certain amount of N2, depending on the O2 content in 5% CO2 incubators. NPY (10-9-10-6 M) increased the RAEC numbers under hypoxic conditions, such as 15 or 10% O2. Peptide YY elicited no proliferative effect on RAEC, and NPY-(18-36) inhibited the NPY-induced increase in cell number, suggesting that NPY increases the RAEC count through the NPY Y3 receptor. Pertussis toxin, U-73122, GF-109203X, myristorylated autocamtide-2-related inhibitory peptide, and wort-mannin inhibited the NPY-induced proliferation of RAEC concentration dependently. DY9760e little affected the proliferation caused by NPY. ML-9 and imatinib actually enhanced the NPY-induced proliferation of cells. These results indicated that the NPY Y3 receptor is coupled with Gi protein, and that NPY-induced increases in RAEC proliferation are mediated by phospholipase C-protein kinase C and/or phosphatidylinositol 3-kinase pathways. In intracellular Ca2+-calmodulin-dependent pathways, calmodulin-dependent protein kinase II partly participates in the NPY-induced cell proliferation. Regarding the previously reported effect of NPY on the permeability of RAEC monolayers to large molecules, it is probable that protein kinase C and phosphatidylinositol 3-kinase pathways are activated for both permeability and cell proliferation induced by NPY under hypoxia, relevant to new insights into the roles of NPY in ischemia-hypoxia.
AB - The present study was undertaken to determine whether neuropeptide Y (NPY) induces proliferation of rat aortic endothelial cells (RAECs). Since NPY increased the permeability of RAEC monolayers to large molecules via the NPY Y3 receptor, RAEC proliferation has been evaluated in terms of NPY-receptor subtypes and also intracellular mechanisms. RAECs were incubated with gases containing 20, 15, or 10% O2 and a certain amount of N2, depending on the O2 content in 5% CO2 incubators. NPY (10-9-10-6 M) increased the RAEC numbers under hypoxic conditions, such as 15 or 10% O2. Peptide YY elicited no proliferative effect on RAEC, and NPY-(18-36) inhibited the NPY-induced increase in cell number, suggesting that NPY increases the RAEC count through the NPY Y3 receptor. Pertussis toxin, U-73122, GF-109203X, myristorylated autocamtide-2-related inhibitory peptide, and wort-mannin inhibited the NPY-induced proliferation of RAEC concentration dependently. DY9760e little affected the proliferation caused by NPY. ML-9 and imatinib actually enhanced the NPY-induced proliferation of cells. These results indicated that the NPY Y3 receptor is coupled with Gi protein, and that NPY-induced increases in RAEC proliferation are mediated by phospholipase C-protein kinase C and/or phosphatidylinositol 3-kinase pathways. In intracellular Ca2+-calmodulin-dependent pathways, calmodulin-dependent protein kinase II partly participates in the NPY-induced cell proliferation. Regarding the previously reported effect of NPY on the permeability of RAEC monolayers to large molecules, it is probable that protein kinase C and phosphatidylinositol 3-kinase pathways are activated for both permeability and cell proliferation induced by NPY under hypoxia, relevant to new insights into the roles of NPY in ischemia-hypoxia.
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U2 - 10.1152/ajpheart.00886.2006
DO - 10.1152/ajpheart.00886.2006
M3 - Article
C2 - 17400722
AN - SCOPUS:34547895112
SN - 0363-6135
VL - 293
SP - H959-H967
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
IS - 2
ER -