TY - JOUR
T1 - The diurnal periodicity of hexose transporter mRNA and protein levels in the rat jejunum
T2 - Role of vagal innervation
AU - Houghton, Scott G.
AU - Zarroug, Abdalla E.
AU - Duenes, Judith A.
AU - Fernandez-Zapico, Martin E.
AU - Sarr, Michael G.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2006/4
Y1 - 2006/4
N2 - Background: Protein and messenger RNA (mRNA) levels of the hexose transporters sodium-dependent glucose transporter-1, glucose transporter 2, and glucose transporter 5 follow a (daily) diurnal rhythm in rat jejunum. Because vagal innervation mediates the diurnal activity of other proteins in the rat small bowel, we hypothesized that the diurnal variation of mRNA and protein levels of these hexose transport proteins are mediated by vagal innervation. Methods: Forty-eight rats kept in a strictly maintained, alternating 12-hour light-dark room underwent either sham laparotomy (n = 24) or bilateral total abdominal vagotomy (n = 24). Four weeks postoperatively, jejunal mucosa was harvested from 6 rats in each group at 3 am, 9 am, 3 pm and 9 pm; mRNA levels were determined by reverse transcription real-time polymerase chain reaction and protein levels by semiquantitative Western blot analysis. Transporter mRNA and protein levels were expressed as a ratio to the corresponding mRNA and protein levels of the stably expressed housekeeping gene glyceraldehyde-6-phosphate dehydrogenase. Results: mRNA and protein levels for all 3 hexose transporters showed diurnal variation in sham controls (P ≤ .01 for all). After vagotomy, although mRNA levels of all 3 transporters showed diurnal variation (each P < .01), diurnal variation in all 3 hexose transporter protein levels was abolished (P > .10 for all). Conclusions: Vagal innervation appears to differentially mediate the diurnal changes in hexose transporter mRNA and protein expression in the rat jejunum by posttranscriptional, and/or posttranslational processes.
AB - Background: Protein and messenger RNA (mRNA) levels of the hexose transporters sodium-dependent glucose transporter-1, glucose transporter 2, and glucose transporter 5 follow a (daily) diurnal rhythm in rat jejunum. Because vagal innervation mediates the diurnal activity of other proteins in the rat small bowel, we hypothesized that the diurnal variation of mRNA and protein levels of these hexose transport proteins are mediated by vagal innervation. Methods: Forty-eight rats kept in a strictly maintained, alternating 12-hour light-dark room underwent either sham laparotomy (n = 24) or bilateral total abdominal vagotomy (n = 24). Four weeks postoperatively, jejunal mucosa was harvested from 6 rats in each group at 3 am, 9 am, 3 pm and 9 pm; mRNA levels were determined by reverse transcription real-time polymerase chain reaction and protein levels by semiquantitative Western blot analysis. Transporter mRNA and protein levels were expressed as a ratio to the corresponding mRNA and protein levels of the stably expressed housekeeping gene glyceraldehyde-6-phosphate dehydrogenase. Results: mRNA and protein levels for all 3 hexose transporters showed diurnal variation in sham controls (P ≤ .01 for all). After vagotomy, although mRNA levels of all 3 transporters showed diurnal variation (each P < .01), diurnal variation in all 3 hexose transporter protein levels was abolished (P > .10 for all). Conclusions: Vagal innervation appears to differentially mediate the diurnal changes in hexose transporter mRNA and protein expression in the rat jejunum by posttranscriptional, and/or posttranslational processes.
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U2 - 10.1016/j.surg.2005.09.002
DO - 10.1016/j.surg.2005.09.002
M3 - Article
C2 - 16627065
AN - SCOPUS:33646472627
SN - 0039-6060
VL - 139
SP - 542
EP - 549
JO - Surgery
JF - Surgery
IS - 4
ER -