title: Inhibition of inducible nitric oxide production and iNOS protein expression in lipopolysaccharide-stimulated rat aorta and Raw 264.7 macrophages by ethanol extract of a Chinese herbal medicine formula (RCM-101) for allergic rhinitis.
abstract: OBJECTIVE
  A Chinese herbal formula (RCM-101) has shown to be effective in reducing symptoms of seasonal allergic rhinitis (SAR) in a randomised, placebo-controlled clinical trial. The aim of this study is to investigate the effects of RCM-101 on the actions and synthesis of nitric oxide (NO). l-Arginine-induced endothelium-independent relaxations were studied in rat isolated aorta which was pre-treated with lipopolysaccharide (LPS).
  
  
  METHODS
  NO production and inducible nitric oxide synthase (iNOS) protein expression were studied in LPS and interferon gamma-stimulated murine macrophages (Raw 264.7), measured by NO sensors and Western blotting.
  
  
  RESULTS
  In rat aortic preparations, RCM-101 significantly inhibited endothelium-independent relaxations to l-arginine, but not affected those to sodium nitroprusside (SNP). In Raw 264.7 cells, RCM-101 and some of its individual ingredients (e.g., Radix glycyrrhizae, Radix bupleuri, Radix saposhnikoviae and Atractylodis rhizome macrocephalae) significantly inhibited the NO production and iNOS protein expression.
  
  
  CONCLUSIONS
  The findings indicate that RCM-101 may inhibit inducible NO production by suppressing iNOS. In addition, its inhibitory action of iNOS is likely to be mediated by several key herbal ingredients.
authors.affiliation: The Chinese Medicine Research Group, RMIT University, Bundoora West Campus, Bundoora, Victoria 3083, Australia. george.lenon@rmit.edu.au
authors.forename: George Binh
authors.initials: GB
authors.lastname: Lenon
authors.forename: Chung Guang
authors.initials: CG
authors.lastname: Li
authors.forename: Charlie Changli
authors.initials: CC
authors.lastname: Xue
authors.forename: Francis Chung Kong
authors.initials: FC
authors.lastname: Thien
authors.forename: David Frederick
authors.initials: DF
authors.lastname: Story
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D002460:Cell Line; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D000431:Ethanol / Q000737:chemistry; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects*; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009569:Nitric Oxide / Q000096:biosynthesis / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis* / Q000235:genetics; D009599:Nitroprusside / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D004365:Drugs, Chinese Herbal; D008070:Lipopolysaccharides; D014665:Vasodilator Agents; D009599:Nitroprusside; D009569:Nitric Oxide; D000431:Ethanol; D052247:Nitric Oxide Synthase Type II