A constitutive nitric oxide synthase modulates insulin secretion in the INS-1 cell line.
Mol Cell Endocrinol
; 183(1-2): 41-8, 2001 Oct 25.
Article
em En
| MEDLINE
| ID: mdl-11604223
ABSTRACT
We provide immunocytochemical evidence that the neuronal isoform of constitutive NO synthase (cNOS) is expressed in the rat insulinoma cell line INS-1. Furthermore, using N omega-nitro-L-arginine methyl ester (L-NAME), a pharmacological inhibitor of cNOS activity, we show that this enzyme is implicated in the modulation of insulin secretion in INS-1 cells. Indeed, in the presence of 2.8 mM glucose, L-NAME induced a specific and dose-dependent increase in insulin release, suggesting that cNOS exerts an inhibitory tone on basal insulin secretion. Moreover, L-arginine, the physiological substrate of cNOS, significantly reduced the marked enhancing effect of L-NAME on insulin release and to a lesser extent, at low concentrations, that of 10 mM KCl. L-NAME also potentiated the insulin secretion stimulated by 5.5 and 8.3 mM glucose, but in this case, its effect was not reduced by L-arginine. In conclusion, our data show that the neuronal isoform of cNOS exerts a negative modulation on insulin secretion in INS-1 cells, confirming the previous results obtained in the isolated perfused rat pancreas or pancreatic islets.
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Base de dados:
MEDLINE
Assunto principal:
Óxido Nítrico Sintase
/
NG-Nitroarginina Metil Éster
/
Insulina
Limite:
Animals
Idioma:
En
Revista:
Mol Cell Endocrinol
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Itália