Involvement of Ca2+/calmodulin-dependent protein kinase II in endothelial NO production and endothelium-dependent relaxation.
Nitric oxide (NO) is synthesized from l-arginine by the Ca(2+)/calmodulin-sensitive endothelial NO synthase (NOS) isoform (eNOS). The present study assesses the role of Ca(2+)/calmodulin-dependent protein kinase II (CaMK II) in endothelium-dependent relaxation and NO synthesis. The effects of three CaMK II inhibitors were investigated in endothelium-intact aortic rings of normotensive rats. NO synthesis was assessed by a NO sensor and chemiluminescence in culture medium of cultured porcine aortic endothelial cells stimulated with the Ca(2+) ionophore A23187 and thapsigargin. Rat aortic endothelial NOS activity was measured by the conversion of l-[(3)H]arginine to l-[(3)H]citrulline. Three CaMK II inhibitors, polypeptide 281-302, KN-93, and lavendustin C, attenuated the endothelium-dependent relaxation of endothelium-intact rat aortic rings in response to acetylcholine, A23187, and thapsigargin. None of the CaMK II inhibitors affected the relaxation induced by NO donors. In a porcine aortic endothelial cell line, KN-93 decreased NO synthesis and caused a rightward shift of the concentration-response curves to A23187 and thapsigargin. In rat aortic endothelial cells, KN-93 significantly decreased bradykinin-induced eNOS activity. These results suggest that CaMK II was involved in NO synthesis as a result of Ca(2+)-dependent activation of eNOS.
Schneider
Jean-Christophe
JC
Service de Physiologie-Explorations Fonctionnelles, Centre Hospitalier Universitaire Cochin, Assistance Publique, Hôpitaux de Paris, Université Paris 5, France.
El Kebir
Driss
D
Chéreau
Christiane
C
Lanone
Sophie
S
Huang
Xiao-Lin
XL
De Buys Roessingh
Anthony S
AS
Mercier
Jean-Christophe
JC
Dall'Ava-Santucci
Josette
J
Dinh-Xuan
A Tuan
AT
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D001596:Benzylamines / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002460:Cell Line; D002478:Cells, Cultured; D004558:Electric Stimulation; D004730:Endothelium, Vascular / Q000201:enzymology / Q000378:metabolism* / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015151:Immunoblotting; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000502:physiology; D009126:Muscle Relaxation / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000201:enzymology / Q000502:physiology*; D009569:Nitric Oxide / Q000096:biosynthesis*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III; D010766:Phosphorylation; D051381:Rats; D026423:S-Nitroso-N-Acetylpenicillamine / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D013552:Swine; D019284:Thapsigargin / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology; D000096926:Benzenesulfonamides
D000109:Acetylcholine; D001596:Benzylamines; D000001:Calcimycin; D002118:Calcium; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D004791:Enzyme Inhibitors; D009569:Nitric Oxide; D020030:Nitric Oxide Donors; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; D026423:S-Nitroso-N-Acetylpenicillamine; D013449:Sulfonamides; D019284:Thapsigargin; D014665:Vasodilator Agents; C072105:KN 93; D000096926:Benzenesulfonamides; C496316:Nos3 protein, rat