{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T15:12:20Z","timestamp":1788534740470,"version":"build-2803163510"},"reference-count":30,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T00:00:00Z","timestamp":1638748800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>The duodenal mucosa is regularly exposed to a low osmolality, and recent experiments suggest that hypotonicity increases mucosal permeability in an osmolality-dependent manner. The aim was to examine whether the sympathetic nervous system, via action on \u03b1-adrenoceptors, affects the hypotonicity-induced increase in duodenal mucosal permeability. The duodenum of anaesthetised rats was perfused in vivo with a 50 mM NaCl solution in the presence of adrenergic \u03b1-adrenoceptor drugs. Studied were the effects on mucosal permeability (blood-to-lumen clearance of 51Cr-EDTA), arterial blood pressure, luminal alkalinisation, transepithelial fluid flux, and motility. Hypotonicity induced a six-fold increase in mucosal permeability, a response that was reversible and repeatable. The \u03b12-adrenoceptor agonist clonidine abolished the hypotonicity-induced increase in mucosal permeability, reduced arterial blood pressure, inhibited duodenal motility, and decreased luminal alkalinisation. The \u03b12-adrenoceptor antagonists, yohimbine and idazoxan, prevented the inhibitory effect of clonidine on the hypotonicity-induced increase in mucosal permeability. The \u03b11-agonist phenylephrine or the \u03b11-antagonist prazosin elicited their predicted effect on blood pressure but did not affect the hypotonicity-induced increase in mucosal permeability. None of the \u03b11- or \u03b12-adrenoceptor drugs changed the hypotonicity-induced net fluid absorption. In conclusion, stimulation of the adrenergic \u03b12-adrenoceptor prevents the hypotonicity-induced increase in mucosal permeability, suggesting that the sympathetic nervous system has the capability to regulate duodenal mucosal permeability.<\/jats:p>","DOI":"10.3390\/pharmaceutics13122096","type":"journal-article","created":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T22:18:42Z","timestamp":1638829122000},"page":"2096","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["The Impact of \u03b1-Adrenoceptors in the Regulation of the Hypotonicity-Induced Increase in Duodenal Mucosal Permeability In Vivo"],"prefix":"10.3390","volume":"13","author":[{"given":"John","family":"Sedin","sequence":"first","affiliation":[{"name":"Department of Neuroscience, Division of Physiology, Uppsala University, 75236 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5586-2906","authenticated-orcid":false,"given":"David","family":"Dahlgren","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Division of Physiology, Uppsala University, 75236 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Markus","family":"Sj\u00f6blom","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Division of Physiology, Uppsala University, 75236 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olof","family":"Nylander","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Division of Physiology, Uppsala University, 75236 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"G360","DOI":"10.1152\/ajpgi.00428.2002","article-title":"Hypotonicity-induced increases in duodenal mucosal permeability facilitates adjustment of luminal osmolality","volume":"285","author":"Nylander","year":"2003","journal-title":"Am. 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