Microcirculatory Function during Endotoxemia-A Functional Citrulline-Arginine-NO Pathway and NOS3 Complex Is Essential to Maintain the Microcirculation.
Int J Mol Sci
; 22(21)2021 Nov 03.
Article
em En
| MEDLINE
| ID: mdl-34769369
ABSTRACT
Competition for the amino acid arginine by endothelial nitric-oxide synthase (NOS3) and (pro-)inflammatory NO-synthase (NOS2) during endotoxemia appears essential in the derangement of the microcirculatory flow. This study investigated the role of NOS2 and NOS3 combined with/without citrulline supplementation on the NO-production and microcirculation during endotoxemia. Wildtype (C57BL6/N background; control; n = 36), Nos2-deficient, (n = 40), Nos3-deficient (n = 39) and Nos2/Nos3-deficient mice (n = 42) received a continuous intravenous LPS infusion alone (200 µg total, 18 h) or combined with L-citrulline (37.5 mg, last 6 h). The intestinal microcirculatory flow was measured by side-stream dark field (SDF)-imaging. The jejunal intracellular NO production was quantified by in vivo NO-spin trapping combined with electron spin-resonance (ESR) spectrometry. Amino-acid concentrations were measured by high-performance liquid chromatography (HPLC). LPS infusion decreased plasma arginine concentration in control and Nos3-/- compared to Nos2-/- mice. Jejunal NO production and the microcirculation were significantly decreased in control and Nos2-/- mice after LPS infusion. No beneficial effects of L-citrulline supplementation on microcirculatory flow were found in Nos3-/- or Nos2-/-/Nos3-/- mice. This study confirms that L-citrulline supplementation enhances de novo arginine synthesis and NO production in mice during endotoxemia with a functional NOS3-enzyme (control and Nos2-/- mice), as this beneficial effect was absent in Nos3-/- or Nos2-/-/Nos3-/- mice.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arginina
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Citrulina
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Endotoxemia
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NADPH Oxidases
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NADPH Oxidase 2
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Microcirculação
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Óxido Nítrico
Tipo de estudo:
Etiology_studies
Limite:
Animals
Idioma:
En
Revista:
Int J Mol Sci
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Holanda