Regulation of endothelial nitric-oxide synthase (NOS) S-glutathionylation by neuronal NOS: evidence of a functional interaction between myocardial constitutive NOS isoforms
| Autor: | Idigo, W, Reilly, S, Zhang, M, Zhang, Y, Jayaram, R, Carnicer, R, Crabtree, M, Balligand, J, Casadei, B |
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| Přispěvatelé: | UCL - SSS/IREC/FATH - Pôle de Pharmacologie et thérapeutique, UCL - (SLuc) Service de médecine interne générale, UCL - SSS/IREC - Institut de recherche expérimentale et clinique |
| Rok vydání: | 2012 |
| Předmět: |
inorganic chemicals
Nitric Oxide Synthase Type III Xanthine Dehydrogenase Heart Ventricles Muscle Proteins Nitric Oxide Synthase Type I Mice Superoxides Animals Myocytes Cardiac Calcium Signaling Enzyme Inhibitors Phosphorylation Mice Knockout Membrane Glycoproteins Arginase Myocardium Thiourea NADPH Oxidases Isoenzymes NG-Nitroarginine Methyl Ester nervous system Receptors Adrenergic beta-3 NADPH Oxidase 2 cardiovascular system Citrulline Signal Transduction |
| Zdroj: | Journal of Biological Chemistry, Vol. 287, no. 52, p. 43665-43673 (2012) |
| ISSN: | 1083-351X |
| Popis: | Myocardial constitutive No production depends on the activity of both endothelial and neuronal NOS (eNOS and nNOS, respectively). Stimulation of myocardial β(3)-adrenergic receptor (β(3)-AR) produces a negative inotropic effect that is dependent on eNOS. We evaluated whether nNOS also plays a role in β(3)-AR signaling and found that the β(3)-AR-mediated reduction in cell shortening and [Ca(2+)](i) transient amplitude was abolished both in eNOS(-/-) and nNOS(-/-) left ventricular (LV) myocytes and in wild type LV myocytes after nNOS inhibition with S-methyl-L-thiocitrulline. LV superoxide (O(2)(·-)) production was increased in nNOS(-/-) mice and reduced by L-N(ω)-nitroarginine methyl ester (L-NAME), indicating uncoupling of eNOS activity. eNOS S-glutathionylation and Ser-1177 phosphorylation were significantly increased in nNOS(-/-) myocytes, whereas myocardial tetrahydrobiopterin, eNOS Thr-495 phosphorylation, and arginase activity did not differ between genotypes. Although inhibitors of xanthine oxidoreductase (XOR) or NOX2 NADPH oxidase caused a similar reduction in myocardial O(2)(·-), only XOR inhibition reduced eNOS S-glutathionylation and Ser-1177 phosphorylation and restored both eNOS coupled activity and the negative inotropic and [Ca(2+)](i) transient response to β(3)-AR stimulation in nNOS(-/-) mice. In summary, our data show that increased O(2)(·-) production by XOR selectively uncouples eNOS activity and abolishes the negative inotropic effect of β(3)-AR stimulation in nNOS(-/-) myocytes. These findings provide unequivocal evidence of a functional interaction between the myocardial constitutive NOS isoforms and indicate that aspects of the myocardial phenotype of nNOS(-/-) mice result from disruption of eNOS signaling. |
| Databáze: | OpenAIRE |
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