A calcium channel blocker activates both ecto-5(')-nucleotidase and NO synthase in HUVEC.
Since amlodipine, a long-acting Ca channel blocker, increases both NO and adenosine production in canine hearts, we investigated that amlodipine activates both ecto-5(')-nucleotidase responsible for adenosine production and NO synthase (NOS) for NO production in human umbilical venous endothelial cells (HUVECs), and its cellular signaling. We measured activities of ecto-5(')-nucleotidase and NOS in HUVECs in the condition with additions of xanthine (100 microM)+xanthine oxidase (1.6 x 10(-3)U/ml) in the presence or absence of amlodipine (1 x 10(-9)-1 x 10(-6)M). Amlodipine increased both ecto-5(')-nucleotidase and NOS activities. Xanthine+xanthine oxidase deactivated both NOS and ecto-5(')-nucleotidase, and amlodipine increased both activities of NOS and ecto-5(')-nucleotidase by 117+/-33% and 48+/-6%, respectively. Amlodipine phosphorylated p38MAP kinase and that an inhibitor of p38MAP kinase inhibited the amlodipine-induced activation of both NOS and ecto-5(')-nucleotidase. Furthermore, amlodipine increased both adenosine and NO production in the canine ischemic hearts. We concluded that amlodipine activates both NOS and ecto-5(')-nucleotidase via p38MAP kinase in vitro and enhances both NO and adenosine production in vivo.
Asano
Yoshihiro
Y
Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, Suita, Japan. asano@medone.med.osaka-u.ac.jp
Kim
Jiyoong
J
Ogai
Akiko
A
Takashima
Seiji
S
Shintani
Yasunori
Y
Minamino
Tetsuo
T
Kitamura
Soichiro
S
Tomoike
Hitonobu
H
Hori
Masatsugu
M
Kitakaze
Masafumi
M
D017311:Amlodipine / Q000494:pharmacology*; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002478:Cells, Cultured; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D010766:Phosphorylation; D013997:Time Factors; D014471:Umbilical Veins / Q000201:enzymology*; D019820:Xanthine / Q000494:pharmacology; D014969:Xanthine Oxidase / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases
D002121:Calcium Channel Blockers; D004791:Enzyme Inhibitors; D019820:Xanthine; D017311:Amlodipine; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D014969:Xanthine Oxidase; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases