| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0615
It has been
demonstrated in the conscious dog that portal glucose infusion creates
a signal that increases net hepatic glucose uptake and hepatic glycogen
deposition. Experiments leading to an understanding of the mechanism by
which this change occurs will be facilitated if this finding can be
reproduced in the rat. Rats weighing 275-300 g were implanted with
four indwelling catheters (one in the portal vein, one in the left
carotid artery, and two in the right jugular vein) that were
externalized between the scapulae. The rats were studied in a
conscious, unrestrained condition 7 days after surgery, following a
24-h fast. Each experiment consisted of a 30- to 60-min equilibration,
a 30-min baseline, and a 120-min test period. In the test period, a
pancreatic clamp was performed by using somatostatin, insulin, and
glucagon. Glucose was given simultaneously either through the jugular
vein to clamp the arterial blood level at 220 mg/dl (Pe low group) or
at 250 mg/dl (Pe high group), or via the hepatic portal vein (Po group;
6 mg · kg
1 · min1)
and the jugular vein to clamp the arterial blood glucose level to 220 mg/dl. In the test period, the arterial plasma glucagon and insulin
levels were not significantly different in the three groups (36 ± 2, 33 ± 2, and 30 ± 2 pg/ml and 1.34 ± 0.08, 1.37 ± 0.18, and 1.66 ± 0.11 ng/ml in Po, Pe low, and Pe high groups, respectively). The arterial blood glucose levels during the test period
were 224 ± 4 mg/dl for Po, 220 ± 3 for Pe low, and 255 ± 2 for Pe high group. The liver glycogen content (µmol glucose/g liver)
in the two Pe groups was not statistically different (51 ± 7 and 65 ± 8, respectively), whereas the glycogen level in the Po group was
significantly greater (93 ± 9, P < 0.05). Because portal glucose delivery also augments hepatic
glycogen deposition in the rat, as it does in the dogs, mechanistic
studies relating to its function can now be undertaken in this species.
liver; somatostatin; insulin; glucagon; portal signal
This article has been cited by other articles:
|
|
 |
|
  F.-Y. Chueh, C. Malabanan, and O. P. McGuinness Impact of portal glucose delivery on glucose metabolism in conscious, unrestrained mice Am J Physiol Endocrinol Metab, December 1, 2006; 291(6): E1206 - E1211. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Gautier-Stein, C. Zitoun, E. Lalli, G. Mithieux, and F. Rajas Transcriptional Regulation of the Glucose-6-phosphatase Gene by cAMP/Vasoactive Intestinal Peptide in the Intestine: ROLE OF HNF4{alpha}, CREM, HNF1{alpha}, and C/EBP{alpha} J. Biol. Chem., October 20, 2006; 281(42): 31268 - 31278. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Ogihara, W. Kawamura, K. Kasuga, Y. Hayashi, H. Arakawa, and M. Kikuchi Characterization of the portal signal during 24-h glucose delivery in unrestrained, conscious rats Am J Physiol Endocrinol Metab, June 1, 2004; 286(6): E932 - E940. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Fery, L. Tappy, J. Deviere, and E. O. Balasse Comparison of intraduodenal and intravenous glucose metabolism under clamp conditions in humans Am J Physiol Endocrinol Metab, February 1, 2004; 286(2): E176 - E183. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. C. Moore, S. Cardin, D. S. Edgerton, B. Farmer, D. W. Neal, M. Lautz, and A. D. Cherrington Unlike mice, dogs exhibit effective glucoregulation during low-dose portal and peripheral glucose infusion Am J Physiol Endocrinol Metab, February 1, 2004; 286(2): E226 - E233. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Zangeneh, R. Basu, P. Shah, P. Arora, M. Camilleri, and R. A. Rizza Enteral infusion of glucose at rates approximating EGP enhances glucose disposal but does not cause hypoglycemia Am J Physiol Endocrinol Metab, August 1, 2003; 285(2): E280 - E286. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Vella, P. Shah, R. Basu, A. Basu, M. Camilleri, W. F. Schwenk, and R. A. Rizza Effect of enteral vs. parenteral glucose delivery on initial splanchnic glucose uptake in nondiabetic humans Am J Physiol Endocrinol Metab, August 1, 2002; 283(2): E259 - E266. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Fery, J. Deviere, and E. O. Balasse Metabolic handling of intraduodenal vs. intravenous glucose in humans Am J Physiol Endocrinol Metab, August 1, 2001; 281(2): E261 - E268. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
