Publications by authors named "Hirofusa Ajioka"

Aims: Gastroesophageal reflux disease is considered to be caused primarily by gastric juice refluxed into the esophagus. Here, we investigated the possible involvement of host defense mechanisms in the development of acute reflux esophagitis using lafutidine, a histamine H(2) receptor antagonist (H(2)RA) with proven gastric mucosal protective effects.

Methods And Results: The ligation of both the pylorus and the forestomach of SD rats under anesthesia caused hemorrhagic lesions in the esophageal mucosa at 6 h.

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Lafutidine, a histamine H(2) receptor antagonist, exerts gastroprotective effects in addition to gastric antisecretory activity. The gastrointestinal protective effects of lafutidine are mediated by capsaicin-sensitive neurons, where capsaicin excites neurons by opening a member of the transient receptor potential channel family (TRPV1). Since the effect of lafutidine on the intracellular Ca(2+) concentration ([Ca(2+)](i)) in cells has not been elucidated, we investigated the lafutidine response to [Ca(2+)](i) in rat pheochromocytoma PC12 and human endothelial cells.

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Background And Aim: Attachment of Helicobacter pylori to gastric epithelial cells leads to the production of chemokines, such as interleukin-8 (IL-8), which in turn activate and recruit neutrophils to the site of infection. Lafutidine [(+/-)-2-(furfurylsulfinyl)-N-(4-(4-(piperidinomethyl)-2-pyridyl)oxy-(Z)-2-butenyl)acetamide] is a new type of antiulcer drug that possesses an antisecretory action as well as gastroprotective activity, independent of its antisecretory action. In the present study, we examined the effects of lafutidine on H.

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Helicobacter pylori (H. pylori) infection of gastric epithelial cells has been shown to induce interleukin (IL)-8 production, but the signal transduction mechanism leading to IL-8 production has not been clearly defined. Here, we investigate the role of protein kinase C (PKC) in the mechanism of induction of IL-8 release by H.

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Infecting gastric epithelial cells with Helicobacter pylori (H. pylori) has been shown to induce interleukin-8 (IL-8) production, but the signal transduction mechanism leading to IL-8 production is not defined clearly. In the present study, we investigated the molecular mechanism responsible for H.

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1. Capsaicin sensitive afferent nerves play an important role in gastric mucosal defensive mechanisms. Capsaicin stimulates afferent nerves and enhances the release of calcitonin gene-related peptide (CGRP), which seems to be the predominant neurotransmitter of spinal afferents in the rat stomach, exerting many pharmacological effects by a direct mechanism or indirectly through second messengers such as nitric oxide (NO).

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