uu.seUppsala universitets publikasjoner
Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Nitrate, Nitrite and Nitric Oxide in Gastric Mucosal Defense
Uppsala universitet, Medicinska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk cellbiologi.
2008 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

The human stomach normally contains high levels of bioactive nitric oxide (NO). This NO derives from salivary nitrate (NO3-) that is converted to nitrite (NO2-) by oral bacteria and thereafter non-enzymatically reduced in the acidic gastric lumen to NO. Nitrate is a common component in vegetables, and after ingestion it is absorbed in the small intestine. Interestingly, circulating nitrate is then concentrated by the salivary glands. Hence, intake of nitrate-rich vegetables results in high levels of NO in the stomach. The physiological effects of the high concentration of NO gas normally present in the gastric lumen have been hitherto unknown, and the present investigations were therefore conducted to address this issue.

NO produced in the gastric lumen after nitrate ingestion increased gastric mucosal blood flow and the thickness of the firmly adherent mucus layer in the stomach. The blood flow and mucus layer are essential defense mechanisms that protect the mucosa from luminal acid and noxious agents. Nonsteroidal antiinflammatory drugs (NSAID) are commonly prescribed and effective drugs for treating pain and inflammation, but are associated with severe gastrointestinal side effects. We demonstrated that a nitrate-rich diet protects against NSAID-induced gastric damage, as a result of the increased formation of NO in the stomach. We also showed that the gastroprotective effect attributed to nitrate depended completely on conversion of nitrate to nitrite by the bacterial flora colonizing the tongue, and that the oral microflora is therefore important in regulating physiological conditions in the stomach.

In summary, this thesis challenges the current dogma that nitrate intake is hazardous, and on the contrary suggests that dietary nitrate plays a direct role in regulating gastric homeostasis. It is likely that a sufficient supply of nitrate in the diet together with the oral microflora is essential for preventing pathological conditions in the gastrointestinal tract.

sted, utgiver, år, opplag, sider
Uppsala: Acta Universitatis Upsaliensis , 2008. , s. 90
Serie
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine, ISSN 1651-6206 ; 328
Emneord [en]
dietary nitrate, mucus gel layer, mucosal blood flow, mucus thickness, laser-Doppler flowmetry, mucosal damage, intra-vital microscopy, mucosal permeability
HSV kategori
Identifikatorer
URN: urn:nbn:se:uu:diva-8624ISBN: 978-91-554-7152-1 (tryckt)OAI: oai:DiVA.org:uu-8624DiVA, id: diva2:171763
Disputas
2008-05-09, the main building of Uppsala University, Room IV, 13:15
Opponent
Veileder
Tilgjengelig fra: 2008-04-16 Laget: 2008-04-16bibliografisk kontrollert
Delarbeid
1. Nitrite in saliva increases gastric mucosal blood flow and mucus thickness
Åpne denne publikasjonen i ny fane eller vindu >>Nitrite in saliva increases gastric mucosal blood flow and mucus thickness
Vise andre…
2004 Inngår i: The Journal of Clinical Investigation, Vol. 113, nr 1, s. 106-114Artikkel i tidsskrift (Fagfellevurdert) Published
Identifikatorer
urn:nbn:se:uu:diva-96997 (URN)
Tilgjengelig fra: 2008-04-16 Laget: 2008-04-16 Sist oppdatert: 2012-12-14
2.
Posten ble ikke funnet. Det kan skyldes at posten ikke lenger er tilgjengelig eller det er feil id i adressefeltet.
3.
Posten ble ikke funnet. Det kan skyldes at posten ikke lenger er tilgjengelig eller det er feil id i adressefeltet.
4. Oral bacteria regulate gastric mucosal defense via bioactivation of dietary nitrate
Åpne denne publikasjonen i ny fane eller vindu >>Oral bacteria regulate gastric mucosal defense via bioactivation of dietary nitrate
Vise andre…
Manuskript (Annet vitenskapelig)
Identifikatorer
urn:nbn:se:uu:diva-97000 (URN)
Tilgjengelig fra: 2008-04-16 Laget: 2008-04-16 Sist oppdatert: 2012-12-14

Open Access i DiVA

fulltekst(2748 kB)2283 nedlastinger
Filinformasjon
Fil FULLTEXT01.pdfFilstørrelse 2748 kBChecksum MD5
e2cba44576394e752c8920acff8f71a562a5a462444ed46731286b82eb0faca9a3119b3a
Type fulltextMimetype application/pdf
omslag(403 kB)41 nedlastinger
Filinformasjon
Fil COVER01.pdfFilstørrelse 403 kBChecksum MD5
a3083260b523ead95b33e40dbb5a09b2932171cce90f1ae1cb1a6f82ae3b951fb5bb169f
Type coverMimetype application/pdf
Kjøp publikasjonen >>

Av organisasjonen

Søk utenfor DiVA

GoogleGoogle Scholar
Totalt: 2283 nedlastinger
Antall nedlastinger er summen av alle nedlastinger av alle fulltekster. Det kan for eksempel være tidligere versjoner som er ikke lenger tilgjengelige

isbn
urn-nbn

Altmetric

isbn
urn-nbn
Totalt: 8262 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf