Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The sensory neurotoxin, capsaicin, has been used to study the reflex pathway by which gastric acid secretion increases in response to gastric distension in urethane-anesthetized rats. Capsaicin (1%) or vehicle (10% Tween 80 in olive oil) was applied directly to each cervical vagus 7-14 days prior to experiments. Gastric acid secretion was measured in acute gastric fistula rats by continuous intragastric perfusion and back titration or by flushing the gastric contents with saline every 10 min. Gastric acid secretion was stimulated by distension (5 ml for 6 min) or by injection of secretagogues (histamine 5.0 mg/kg s.c., bethanechol 0.5 mg/kg s.c. or pentagastrin 16 micrograms/kg per h i.v.). Gastric distension increased gastric acid secretion 6.2 times over basal gastric acid secretion in vehicle-treated control rats; capsaicin pretreatment significantly reduced this response by 40%. Bilateral cervical vagotomy significantly reduced the secretory response to gastric distension in the vehicle-treated group to a level not significantly different from capsaicin-treated rats. The secretory response to histamine was reduced by 42% in capsaicin-treated rats compared to vehicle pretreatment whereas the responses to pentagastrin and bethanechol were unaltered. These results indicate that capsaicin-sensitive vagal afferent fibers mediate the vagal portion of the secretory response to gastric distension; in addition these afferents play a role in the gastric acid secretory response to histamine.
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PMID:Capsaicin-sensitive vagal afferent fibers and stimulation of gastric acid secretion in anesthetized rats. 259 76

Capsaicin-sensitive afferent neurons are involved in maintaining the integrity of the gastrointestinal mucosa. These neurons are closely apposed to mast cells and could, therefore, lead to their activation. In the present study, the role of capsaicin-sensitive neurons in the pathogenesis of experimental colitis and the possible involvement of mast cells and nitric oxide were evaluated. Rats were treated with capsaicin subcutaneously, 20, 30, and 50 mg/kg, on three consecutive days, a regimen shown to ablate primary afferent neurons. Colitis was induced two weeks later by flushing 2 ml 5% acetic acid into the proximal colon. Control rats received saline, acetic acid, or capsaicin alone. Another group of rats received ketotifen (100 micrograms/100 g body wt x 2/day) intragastrically 48 hr prior to damage induction and thereafter. Rats were sacrificed 24 hr after damage induction, the colon isolated, damage assessed, explants were organ-cultured for 24 hr for determination of nitric oxide generation, and mucosa extracted for determination of leukotriene B4 generation and nitric oxide synthase activity. Significant increases in colonic weight, nitric oxide synthase activity, and nitric oxide and leukotriene B4 generation accompanied the near tripling of acetic acid-induced damage in capsaicin-pretreated rats. Ketotifen pretreatment significantly decreased the macroscopic damage and the increase in colonic weight. The protection provided by ketotifen was accompanied by a significant decrease in leukotriene B4 generation and nitric oxide synthase activity (80%).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ketotifen ameliorates capsaicin-augmented acetic acid-induced colitis. 753 78

The effect of capsaicin on basal and pentagastrin-stimulated gastric acid secretion was investigated in the urethane anaesthetized acute gastric fistula rat. Gastric acid secretion was measured by flushing of the gastric lumen with saline every 15 min or by continuous gastric perfusion. Capsaicin given into the rat stomach at 120 ng x mL(-1) prior to pentagastrin (25 microg x kg(-1), iv) reduced gastric acid secretory response to pentagastrin by 24%. Intravenous (iv) capsaicin (0.5 microg x kg(-1)) did not reduce the pentagastrin-stimulated gastric acid secretion. After topical capsaicin desensitization (3 mg x mL(-1)), basal gastric acid secretion and that in response to pentagastrin (25 microg x kg(-1), intraperitonaeally) was unaltered compared with the control group. Data indicate that topical capsaicin inhibits gastric acid secretion stimulated with pentagastrin in anaesthetized rats.
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PMID:Capsaicin inhibits the pentagastrin-stimulated gastric acid secretion in anaesthetized rats with acute gastric fistula. 1067 25