AJP - Endo Add DOIs to your references at manuscript stage!
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


Am J Physiol Endocrinol Metab 275: E531-E536, 1998;
0193-1849/98 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Castle, A. L.
Right arrow Articles by Ivy, J. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Castle, A. L.
Right arrow Articles by Ivy, J. L.
Vol. 275, Issue 3, E531-E536, September 1998

Amylin-mediated inhibition of insulin-stimulated glucose transport in skeletal muscle

Arthur L. Castle1, Chia-Hua Kuo1, Dong-Ho Han2, and John L. Ivy1

1 Exercise Physiology and Metabolism Laboratory, Department of Kinesiology and Health Education, University of Texas at Austin, Austin, Texas 78712; and 2 Division of Geriatrics and Gerontology, Washington University of Medicine, St. Louis, Missouri 63110

We examined the effects of amylin on 3-O-methyl-D-glucose (3-O-MG) transport in perfused rat hindlimb muscle under hyperinsulinemic (350 µU/ml, 2,100 pmol/l) conditions. Amylin at 100 nmol/l concentration inhibited 3-O-MG transport relative to control in all three basic muscle fiber types. Transport decreased in slow-twitch oxidative (from 5.65 ± 1.13 to 3.46 ± 0.71 µmol · g-1 · h-1), fast-twitch oxidative (from 6.84 ± 0.90 to 4.84 ± 0.76 µmol · g-1 · h-1), and fast-twitch glycolytic (from 1.27 ± 0.20 to 0.60 ± 0.05 µmol · g-1 · h-1) muscle. Amylin inhibition of insulin-stimulated glucose transport in skeletal muscle was accompanied by a 433 ± 72% increase in intracellular glucose 6-phosphate (G-6-P) despite the absence of extracellular glucose. The source of hexose units for the formation and maintenance of G-6-P was likely glycogen. Amylin increased glycogenolysis, increased lactate formation, and decreased glycogen synthase activity. Furthermore, the kinetics of glycogen synthase suggest that this enzyme may control intracellular G-6-P concentration. Despite the large increase in G-6-P, no detectable increase in uridine diphosphate-N-acetylhexosamines occurred, suggesting that the proposed glucosamine pathway may not be involved in transport inhibition. However, decreases in uridine diphosphate hexoses were detected. Therefore, uridine or hexosamine-based metabolites may be involved in amylin action.

glucosamine; glycogen synthase; glucose 6-phosphate; lactate; uridine diphosphate-N-acetylhexosamine; uridine diphosphate hexose


This article has been cited by other articles:


Home page
DiabetesHome page
C. S. Choi, F. N. Lee, and J. H. Youn
Free Fatty Acids Induce Peripheral Insulin Resistance Without Increasing Muscle Hexosamine Pathway Product Levels in Rats
Diabetes, February 1, 2001; 50(2): 418 - 424.
[Abstract] [Full Text]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online