title: Expression of endothelial constitutive nitric oxide synthase mRNA in gastrointestinal mucosa and its downregulation by endotoxin.
abstract: Endothelial nitric oxide exerts local vasodilatory actions in the gastrointestinal (GI) microvasculature and is proposed to play a role in enteric vasomotor regulation. The aims of this study were to characterize the tissue distribution of mRNA for endothelial nitric oxide synthase (NOS-III) and to examine its response to endotoxin challenge in vivo. We demonstrate the expression of NOS-III mRNA and protein in mucosa throughout the gastrointestinal tract and show for the first time that NOS-III mRNA expression in the GI mucosa was down-regulated in the rats treated with endotoxin. The ubiquitous expression of NOS-III mRNA in digestive tissues is consistent with the proposed role of NOS-III in the physiology of the gastrointestinal tract. The decreased NOS-III mRNA, in parallel to induction of inducible NOS (NOS-II) mRNA, may contribute to the impaired endothelium-dependent relaxation and damaged mucosal integrity during sepsis.
authors.affiliation: Department of Pediatric Surgery, Osaka University Medical School, Suita, Japan. kchen@pedsurg.med.osaka-u.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Chen
authors.forename: M
authors.initials: M
authors.lastname: Inoue
authors.forename: M
authors.initials: M
authors.lastname: Wasa
authors.forename: M
authors.initials: M
authors.lastname: Fukuzawa
authors.forename: S
authors.initials: S
authors.lastname: Kamata
authors.forename: A
authors.initials: A
authors.lastname: Okada
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D004064:Digestive System / Q000201:enzymology; D004730:Endothelium, Vascular / Q000201:enzymology*; D004731:Endotoxins / Q000494:pharmacology*; D015971:Gene Expression Regulation, Enzymologic; D007413:Intestinal Mucosa / Q000201:enzymology*; D008168:Lung / Q000201:enzymology; D008297:Male; D009206:Myocardium / Q000201:enzymology; D019001:Nitric Oxide Synthase / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism*; D051381:Rats; D014018:Tissue Distribution
chemical_list: D004731:Endotoxins; D012333:RNA, Messenger; D019001:Nitric Oxide Synthase