BACKGROUND: Helicobacter pylori produces ammonia in the stomach from urea. The present study was undertaken to clarify whether ammonia has an etiological role in H. pylori-associated gastric mucosal atrophy. METHODS: Ammonia at 0.01% was administered as drinking water for 8 weeks and mucosal cell migration rate and cell proliferation were investigated in rat stomach. RESULTS: Long-term administration of 0.01% ammonia for 4-8 weeks decreased mucosal thickness in the antrum but not in the body. Acceleration of cell migration preceded the occurrence of mucosal atrophy. Labeling indices in both antral and body mucosa significantly increased in all ammonia-treated groups, compared with those of the control group. In the antrum, the proliferative zone was significantly enlarged as mucosal atrophy developed, whereas, in body mucosa, enlargement of the proliferative zone occurred despite the absence of mucosal atrophy. CONCLUSION: Ammonia at 0.01% accelerates epithelial migration, especially in the antrum, leading to mucosal atrophy. Acceleration of epithelial proliferation occurs during the development of mucosal atrophy.
BACKGROUND:Helicobacter pylori produces ammonia in the stomach from urea. The present study was undertaken to clarify whether ammonia has an etiological role in H. pylori-associated gastric mucosal atrophy. METHODS:Ammonia at 0.01% was administered as drinking water for 8 weeks and mucosal cell migration rate and cell proliferation were investigated in rat stomach. RESULTS: Long-term administration of 0.01% ammonia for 4-8 weeks decreased mucosal thickness in the antrum but not in the body. Acceleration of cell migration preceded the occurrence of mucosal atrophy. Labeling indices in both antral and body mucosa significantly increased in all ammonia-treated groups, compared with those of the control group. In the antrum, the proliferative zone was significantly enlarged as mucosal atrophy developed, whereas, in body mucosa, enlargement of the proliferative zone occurred despite the absence of mucosal atrophy. CONCLUSION:Ammonia at 0.01% accelerates epithelial migration, especially in the antrum, leading to mucosal atrophy. Acceleration of epithelial proliferation occurs during the development of mucosal atrophy.
Authors: V Ricci; C Ciacci; R Zarrilli; P Sommi; M K Tummuru; C Del Vecchio Blanco; C B Bruni; T L Cover; M J Blaser; M Romano Journal: Infect Immun Date: 1996-07 Impact factor: 3.441
Authors: H Iishi; M Tatsuta; M Baba; T Mikuni; R Yamamoto; K Iseki; H Yano; H Uehara; A Nakaizumi Journal: J Gastroenterol Date: 1997-08 Impact factor: 7.527