title: Inducible Nitric Oxide Synthase in the Duodenal Mucosa Is Associated with Mast Cell Degranulation in Patients with Functional Dyspepsia.
abstract: OBJECTIVE
  Functional dyspepsia (FD) is a clinical syndrome with chronic gastroduodenal symptoms without noticeable organic or systemic diseases. According to the Rome III consensus, FD can be subdivided into PDS (postprandial distress syndrome) and EPS (epigastric pain syndrome). Neurotransmitters are involved in the development and pathology of FD. However, the expression profiles of neurotransmitters in FD patients are not clear. This study aimed to investigate the expression profile of neurotransmitters in the duodenal mucosa of FD patients.
  
  
  METHODS
  A total of 48 FD patients treated at our hospital were included in this study: 23 patients with PDS and 25 patients with EPS. Another 21 healthy volunteers served as normal controls. The duodenal mucosa was biopsied with gastroscopy and examined with immunohistochemical staining against serotonin, substance P, inducible nitric oxide synthase (iNOS), and vasoactive intestinal peptide (VIP). Mast cells were identified with toluidine blue staining.
  
  
  RESULTS
  The duodenal iNOS levels were significantly higher in PDS patients than the normal controls (P<0.05). The expression of serotonin, substance P, and VIP did not differ significantly among the groups. Mast cell counts and the percentage of mast cells with degranulation were significantly higher in PDS and EPS patients than normal controls (P<0.001) In addition, iNOS expression levels were positively correlated with percentage of degranulating mast cells (r=0.321, P=0.008).
  
  
  CONCLUSIONS
  In conclusion, duodenal iNOS may be involved in the pathogenesis of PDS.
authors.affiliation: Department of Gastroenterology, Tai'an Central Hospital, Tai'an, China.
authors.forename: Hai-Peng
authors.initials: HP
authors.lastname: Yuan
authors.affiliation: Department of Gastroenterology, Tai'an Central Hospital, Tai'an, China.
authors.forename: Xiao-Pei
authors.initials: XP
authors.lastname: Li
authors.affiliation: Department of Gastroenterology, Tai'an Central Hospital, Tai'an, China.
authors.forename: Wen-Rong
authors.initials: WR
authors.lastname: Yang
authors.affiliation: Department of Gastroenterology, Tai'an Central Hospital, Tai'an, China.
authors.forename: Fu-Kang
authors.initials: FK
authors.lastname: Li
authors.affiliation: Department of Gastroenterology, Shandong University Qilu Hospital, Jinan, China yanqingli1@126.com.
authors.forename: Yan-Qing
authors.initials: YQ
authors.lastname: Li
mesh_terms: D015746:Abdominal Pain / Q000201:enzymology / Q000473:pathology; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015550:Cell Degranulation / Q000502:physiology*; D004386:Duodenum / Q000201:enzymology / Q000473:pathology; D004415:Dyspepsia / Q000473:pathology*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000201:enzymology* / Q000473:pathology; D008297:Male; D008407:Mast Cells / Q000502:physiology*; D008875:Middle Aged; D018377:Neurotransmitter Agents / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism*; D019518:Postprandial Period; D011446:Prospective Studies; D012701:Serotonin / Q000378:metabolism; D013373:Substance P / Q000378:metabolism; D013577:Syndrome
chemical_list: D018377:Neurotransmitter Agents; D012701:Serotonin; D013373:Substance P; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II
keywords: degranulation; duodenal mucosal; functional dyspepsia; immune cells; neurotransmitter