Regulation of. beta. -cell glucose transporter gene expression

Journal Article · Fri Jun 01 00:00:00 EDT 1990 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.87.11.4088· OSTI ID:5393640

Chen, Ling; Alam, Tausif; Johnson, J H; Unger, R H ^[1]; Hughes, S; Newgard, C B ^[2]

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1. Univ. of Texas Southwestern Medical Center, Dallas (USA) Department of Veterans Affairs Medical Center, Dallas, TX (USA)
2. Univ. of Texas Southwestern Medical Center, Dallas (USA)

It has been postulated that a glucose transporter of {beta} cells (GLUT-2) may be important in glucose-stimulated insulin secretion. To determine whether this transporter is constitutively expressed or regulated, the authors subjected conscious unrestrained Wistar rats to perturbations in glucose homeostasis and quantitated {beta}-cell GLUT-2 mRNA by in situ hybridization. After 3 hr of hypoglycemia, GLUT-2 and proinsulin mRNA signal densities were reduced by 25% of the level in control rats. After 4 days, GLUT-2 and proinsulin mRNA densities were reduced by 85% and 65%, respectively. After 12 days of hypoglycemia, the K{sub m} for 3-O-methyl-D-glucose transport in isolated rat islets, normally 18-20 mM, was 2.5 mM. This provides functional evidence of a profound reduction of high K{sub m} glucose transporter in {beta} cells. In contrast, GLUT-2 was only slightly reduced by hypoglycemia in liver. To determine the effect of prolonged hyperglycemia, they also infused animals with 50% (wt/vol) glucose for 5 days. Hyperglycemic clamping increased GLUT-2 mRNA by 46% whereas proinsulin mRNA doubled. They conclude that GLUT-2 expression in {beta} cells, but not liver, is subject to regulation by certain perturbations in blood glucose homeostasis.

• OSTI ID: 5393640
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (United States) Vol. 87:11; ISSN 0027-8424; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALDEHYDES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CARBOHYDRATES
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DISEASES
DNA HYBRIDIZATION
EVEN-ODD NUCLEI
GENE REGULATION
GLANDS
GLUCOSE
HEXOSES
HOMEOSTASIS
HORMONES
HYBRIDIZATION
HYPERGLYCEMIA
INSULIN
ISOTOPES
LIGHT NUCLEI
LIVER
MAMMALS
MEMBRANE PROTEINS
MESSENGER-RNA
METABOLIC DISEASES
MONOSACCHARIDES
NUCLEI
NUCLEIC ACIDS
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
PATHOGENESIS
PEPTIDE HORMONES
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PROTEINS
RADIOISOTOPES
RATS
RECEPTORS
RNA
RODENTS
SACCHARIDES
SULFUR 35
SULFUR ISOTOPES
VERTEBRATES