Submit Data |  Help |  Video Tutorials |  News |  Publications |  FTP Download |  REST API |  Citing RGD |  Contact   

Circadian regulation of electrolyte absorption in the rat colon.

Authors: Sotak, M  Polidarova, L  Musilkova, J  Hock, M  Sumova, A  Pacha, J 
Citation: Sotak M, etal., Am J Physiol Gastrointest Liver Physiol. 2011 Dec;301(6):G1066-74. doi: 10.1152/ajpgi.00256.2011. Epub 2011 Sep 8.
Pubmed: (View Article at PubMed) PMID:21903759
DOI: Full-text: DOI:10.1152/ajpgi.00256.2011

The intestinal transport of nutrients exhibits distinct diurnal rhythmicity, and the enterocytes harbor a circadian clock. However, temporal regulation of the genes involved in colonic ion transport, i.e., ion transporters and channels operating in absorption and secretion, remains poorly understood. To address this issue, we assessed the 24-h profiles of expression of genes encoding the sodium pump (subunits Atp1a1 and Atp1b1), channels (alpha-, beta-, and gamma-subunits of Enac and Cftr), transporters (Dra, Ae1, Nkcc1, Kcc1, and Nhe3), and the Na(+)/H(+) exchanger (NHE) regulatory factor (Nherf1) in rat colonic mucosa. Furthermore, we investigated temporal changes in the spatial localization of the clock genes Per1, Per2, and Bmal1 and the genes encoding ion transporters and channels along the crypt axis. In rats fed ad libitum, the expression of Atp1a1, gammaEnac, Dra, Ae1, Nhe3, and Nherf1 showed circadian variation with maximal expression at circadian time 12, i.e., at the beginning of the subjective night. The peak gammaEnac expression coincided with the rise in plasma aldosterone. Restricted feeding phase advanced the expression of Dra, Ae1, Nherf, and gammaEnac and decreased expression of Atp1a1. The genes Atp1b1, Cftr, alphaEnac, betaEnac, Nkcc1, and Kcc1 did not show any diurnal variations in mRNA levels. A low-salt diet upregulated the expression of betaEnac and gammaEnac during the subjective night but did not affect expression of alphaEnac. Similarly, colonic electrogenic Na(+) transport was much higher during the subjective night than the subjective day. These findings indicate that the transporters and channels operating in NaCl absorption undergo diurnal regulation and suggest a role of an intestinal clock in the coordination of colonic NaCl absorption.


Gene Ontology Annotations
Objects Annotated

Additional Information

CRRD Object Information
CRRD ID: 10450532
Created: 2016-01-15
Species: All species
Last Modified: 2016-01-15
Status: ACTIVE


RGD is funded by grant HL64541 from the National Heart, Lung, and Blood Institute on behalf of the NIH.