Differential distribution of nitric oxide synthase between cell fractions isolated from the rat gastric mucosa

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Abstract

Cells isolated from the rat gastric mucosa were resolved into two fractions on a percoll density gradient, and into five fractions using counterflow centrifugation (elutriation). Ca2+-dependent nitric oxide synthase (NOS) activity was found in the high density percoll fraction but not in the parietal cell enriched low density fraction. This activity was inhibited by NG-monomethyl-L-arginine with an IC50 of 3.7μM. Cells in the elutriator fraction rich in mucous-epithelial cells exhibited the highest NOS activity, while the smaller cell fractions had no detectable NOS yet had the highest basal release of prostaglandin E2. The parietal cell enriched elutriator fraction again had low NOS activity. The activity of a constitutive NOS in the mucous-cell fraction may indicate a role of NO in the regulation of epithelial cell integrity or secretion.

References (11)

  • S. Moncada et al.

    Pharmacol. Rev

    (1991)
  • R.G. Knowles et al.

    Biochem. J

    (1990)
  • B.J.R. Whittle et al.

    Gastroenterology

    (1991)
  • J.M. Pique et al.

    Eur. J. Pharmacol

    (1989)
  • B.J.R. Whittle et al.

    Br. J. Pharmacol

    (1990)
There are more references available in the full text version of this article.

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  • Regulatory mechanism of duodenal bicarbonate secretion: Roles of endogenous prostaglandins and nitric oxide

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    Citation Excerpt :

    At present, how acidification stimulates the release of NO in the duodenum or which cell type is responsible for the release remains unknown. Various types of cells including surface epithelial cells, enteric neurons as well as endothelial cells are capable of producing NO. Brown et al. (1992) reported that the cells in the elutriator fraction rich in mucous-epithelial cells exhibit the highest activity of the constitutive type of NO synthase (cNOS) in the stomach, distributing in parallel with the NADPH-dependent diaphorase activity. On the other hand, it is believed that the acid-induced HCO3− secretion is mediated via an axonal reflex pathway, in addition to endogenous PGs and NO (Hogan et al., 1993).

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