AIM: To investigate the mechanisms underlying the reduction in gastric blood flow induced by a luminal water extract of Helicobacter pylori (HPE). METHODS: The stomachs of isoflurane-anesthetized mice were exteriorized, and the mucosal surface exposed. Blood flow was measured with the laser-Doppler technique, and systemic arterial blood pressure monitored. C57BL/6 mice were exposed to water extract produced from H pylori strain 88-23. To investigate the role of a nerve- or iNOS-mediated pathway, we used intraluminal lidocaine and iNOS-/- mice. Blood flow response to the endogenous nitric oxide synthase inhibitor asymmetric dimethyl arginine (ADMA) was also assessed. RESULTS: In wild-type mice, HPE decreased mucosal blood flow by approximately 30%. This reduction was abolished in iNOS-deficient mice, and by pre-treatment with lidocaine. Luminally applied ADMA resulted in reduction in blood flow similar to that observed in wild-type mice exposed to HPE. CONCLUSION: A H pylori water extract reduces gastric mucosal blood flow acutely through iNOS- and nerve-mediated pathways.
AIM: To investigate the mechanisms underlying the reduction in gastric blood flow induced by a luminal water extract of Helicobacter pylori (HPE). METHODS: The stomachs of isoflurane-anesthetized mice were exteriorized, and the mucosal surface exposed. Blood flow was measured with the laser-Doppler technique, and systemic arterial blood pressure monitored. C57BL/6 mice were exposed to water extract produced from H pylori strain 88-23. To investigate the role of a nerve- or iNOS-mediated pathway, we used intraluminal lidocaine and iNOS-/- mice. Blood flow response to the endogenous nitric oxide synthase inhibitor asymmetric dimethyl arginine (ADMA) was also assessed. RESULTS: In wild-type mice, HPE decreased mucosal blood flow by approximately 30%. This reduction was abolished in iNOS-deficient mice, and by pre-treatment with lidocaine. Luminally applied ADMA resulted in reduction in blood flow similar to that observed in wild-type mice exposed to HPE. CONCLUSION: A H pyloriwater extract reduces gastric mucosal blood flow acutely through iNOS- and nerve-mediated pathways.
Authors: S Fu; K S Ramanujam; A Wong; G T Fantry; C B Drachenberg; S P James; S J Meltzer; K T Wilson Journal: Gastroenterology Date: 1999-06 Impact factor: 22.682
Authors: I Castagliuolo; J T LaMont; R Letourneau; C Kelly; J C O'Keane; A Jaffer; T C Theoharides; C Pothoulakis Journal: Gastroenterology Date: 1994-09 Impact factor: 22.682
Authors: J D MacMicking; C Nathan; G Hom; N Chartrain; D S Fletcher; M Trumbauer; K Stevens; Q W Xie; K Sokol; N Hutchinson Journal: Cell Date: 1995-05-19 Impact factor: 41.582