Functional evidence for involvement of bumetanide-sensitive Na+K+2CI- cotransport in the hepatoportal Na+ receptor of the Sprague-Dawley rat.
To investigate mechanisms involved in hepatoportal Na+ sensing, responses of hepatic afferent nerve activity (HANA) to intraportal hypertonic NaCl injection were measured before, and after, intraportal infusion of inhibitors of Na+ transport systems. HANA increased in response to the intraportal injection of 0.75 M NaCl in a dose-dependent manner. The HANA response was not affected by amiloride or 4-acetamido-4'-isothiocyanato-stilbene-2,2'-disulfonic acid (SITS), but was suppressed in a dose-dependent manner by intraportal infusion of ouabain, furosemide, or bumetanide. These results indicate that the hepatoportal Na+ receptor senses the Na+ concentration via the bumetanide-sensitive Na+K+2Cl- cotransporter.
D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000494:pharmacology; D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D002034:Bumetanide / Q000494:pharmacology*; D002352:Carrier Proteins / Q000187:drug effects* / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005665:Furosemide / Q000494:pharmacology; D008099:Liver / Q000294:innervation / Q000378:metabolism*; D008297:Male; D009424:Nervous System Physiological Phenomena / Q000187:drug effects; D010042:Ouabain / Q000494:pharmacology; D011168:Portal System / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011956:Receptors, Cell Surface / Q000378:metabolism*; D012462:Saline Solution, Hypertonic / Q000494:pharmacology; D012964:Sodium / Q000378:metabolism*; D028021:Sodium-Potassium-Chloride Symporters