Functional evidence for involvement of bumetanide-sensitive Na super(+)K super(+)2Cl super(-) cotransport in the hepatoportal Na super(+) receptor of the Sprague-Dawley rat

• Published in: Neuroscience letters Vol. 264; no. 1-3; pp. 65 - 68
• Main Authors: Morita, H, Fujiki, N, Hagiike, M, Yamaguchi, O, Lee, K
• Format: Journal Article
• Language: English
• Published: 01.04.1999
• ISSN: 0304-3940
• DOI: 10.1016/S0304-3940(99)00157-3

To investigate mechanisms involved in hepatoportal Na super(+) sensing, responses of hepatic afferent nerve activity (HANA) to intraportal hypertonic NaCl injection were measured before, and after, intraportal infusion of inhibitors of Na super(+) 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 theta -isothiocyanato-stilbene-2,2 theta -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 super(+) receptor senses the Na super(+) concentration via the bumetanide-sensitive Na super(+)K super(+)2Cl super(-) cotransporter.