Evidence for the presence of glucose cycling in pancreatic islets of the ob/ob mouse

Journal Article · Thu Jun 15 04:00:00 EDT 1989 · J. Biol. Chem.; (United States)

OSTI ID:5933889

Khan, A; Chandramouli, V; Ostenson, C G; Ahren, B; Schumann, W C; Loew, H L; Landau, B R; Efendic, S

Pancreatic islets from ob/ob mice incubated with /sub 3/H/sub 2/O and 5.5 mM glucose formed /sup 3/H-labeled glucose, 74 picoatoms incorporated/islet/h. Sixty-three percent of the 3H was bound to carbon 2 of the glucose. The amount of glucose-6-P dephosphorylated to glucose, determined from this incorporation, was 48 pmol/islet/h. Glucose utilization, measured by the formation of /sup 3/H/sub 2/O from (5-/sup 3/H)glucose, was 72 pmol/islet/h. The amount of glucose dephosphorylated was then about 40% of that phosphorylated. Thus, glucose-6-P is dephosphorylated to glucose to a significant extent by intact islets in vitro and presumably by the beta cells of the islets. The extent of this glucose cycling, i.e. glucose----glucose-6-P----glucose, may play a role in determining the extent of glucose-induced insulin secretion.

• Research Organization: Karolinska Hospital, Stockholm (Sweden)
• OSTI ID: 5933889
• Journal Information: J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 264:17; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALDEHYDES
ANIMALS
BODY
CARBOHYDRATES
CHEMICAL REACTIONS
DIGESTIVE SYSTEM
ENDOCRINE GLANDS
GLANDS
GLUCOSE
HEXOSES
HORMONES
HYDROGEN COMPOUNDS
IN VITRO
INSULIN
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
METABOLISM
MICE
MONOSACCHARIDES
ORGANIC COMPOUNDS
ORGANS
OXYGEN COMPOUNDS
PANCREAS
PEPTIDE HORMONES
PHOSPHORYLATION
RODENTS
SACCHARIDES
SECRETION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES
WATER