Capsaicin-sensitive vagal afferents contribute to gastric acid and vascular responses to intracisternal TRH analog

doi:10.1016/0196-9781(90)90196-C

Peptides

Volume 11, Issue 4, July–August 1990, Pages 789-795

https://doi.org/10.1016/0196-9781(90)90196-C Get rights and content

Abstract

Central injection of TRH or its stable analog, RX77368, produces a vagal cholinergic stimulation of gastric acid secretion, mucosal blood flow and motor function. In the present study, we have investigated the contribution of capsaicin-sensitive vagal afferent fibers to the gastric responses to intracisternal injection of RX77368. Gastric acid secretion, measured in acute gastric fistula rats anesthetized with urethane,in response to intracisternal injection of RX77368 (3–30 ng) was reduced by 21–65% by perineural pretreatment of the vagus nerves with capsaicin 10–20 days before experiments. The increase in gastric mucosal blood flow measured by hydrogen gas clearance induced by intracisternal injection of RX77368 (30 ng) was also reduced by 65% in capsaicin-pretreated rats. In contrast, increases in gastric motor function measured manometrically or release of gastric luminal serotonin in response to intracisternal injection of RX77368 (3–30 ng) were unaltered by capsaicin pretreatment. The mechanism by which vagal afferent fibers contribute to the secretory and blood flow responses to the stable TRH analog is unclear at present, but it is possible that the decrease in gastric mucosal blood flow by lesion of capsaicin-sensitive vagal afferents limits the secretory response.

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ArticleCapsaicin-sensitive vagal afferents contribute to gastric acid and vascular responses to intracisternal TRH analog

Abstract

Peptides

Neuroscience

Gastroenterology

J. Auton. Nerv. System

Jpn. J. Pharmacol.

Gastroenterology

Brain Res.

Eur. J. Pharmacol.

Neurosci. Lett.

Regul. Pept.

Regul. Pept.

Peptides

Comput. Biol. Med.

Gastroenterology

Increase in gastric secretion induced by 2-deoxy-D-glucose is impaired in capsaicin pretreated rats

Br. J. Pharmacol.

Medullary sites of TRH analogue stimulation of gastric contractility in the rat

Am. J. Physiol.

Physiology of the gastric circulation

Afferent nerve-mediated protection against deep mucosal damage in the rat stomach

Gastroenterology

Article
Capsaicin-sensitive vagal afferents contribute to gastric acid and vascular responses to intracisternal TRH analog