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PubMed · 9753272

Decrease in gastric sensitivity to distension by 5-HT1A receptor agonists in rats.

M L Rouzade·J Fioramonti·L Bueno
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Abstract

Using an in vivo model for evaluation of gastric sensitivity in awake rats, we aimed to determine whether 5-hydroxytryptamine 1A (5-HT1A) agonists modify pain threshold and gastric compliance specifically through 5-HT1A receptors. Isobaric gastric distensions were performed with a barostat using steps of 5 mm Hg in male rats equipped with a gastric balloon and electrodes implanted in the neck muscles. Gastric distension at 15 or 20 mm Hg induced a typical posture associated with contractions of the neck muscles. Rats received drugs 30 min before gastric distension. The 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), administered intraperitoneally (0.5 mg/kg) increased gastric pain threshold and gastric tone. These effects were reproduced when administered centrally (0.05 mg/kg) and blocked by intracerebroventricular administration of the 5-HT1A antagonist WAY 100635. Flesinoxan (4 mg/kg, intraperitoneally), another 5-HT1A agonist reproduced the effects of 8-OH-DPAT on pain threshold and gastric tone and the alpha2-receptor antagonist yohimbine did not modify the action of 8-OH-DPAT. Our results indicate that activation of 5-HT1A receptors at the level of the central nervous system increases gastric tone and decreases gastric sensitivity to distension.

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8-Hydroxy-2-(di-n-propylamino)tetralinAdrenergic alpha-AntagonistsAnimalsMalePain ThresholdPiperazinesPyridinesRatsRats, WistarSerotonin AntagonistsSerotonin Receptor AgonistsStomachYohimbineJournal Article

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BibTeXRIS

M L Rouzade, J Fioramonti, L Bueno. 1998. Decrease in gastric sensitivity to distension by 5-HT1A receptor agonists in rats.. https://doi.org/10.1023/a%3A1018859214758

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