Decreased insulin secretory response of pancreatic islets during culture in the presence of low glucose is associated with diminished /sup 45/Ca/sup 2 +/ net uptake, NADPH/NADP/sup +/ and GSH/GSSG ratios

Journal Article · Fri Jan 01 04:00:00 EST 1988 · Life Sci.; (United States)

DOI:https://doi.org/10.1016/0024-3205(88)90310-4· OSTI ID:6945493

Verspohl, E J; Kaiser, P; Wahl, M; Ammon, H P.T.

In isolated rat pancreatic islets maintained at a physiologic glucose concentration (5.6 mM) the effect of glucose on parameters which are known to be involved in the insulin secretion coupling such as NADPH, reduced glutathione (GSH), /sup 86/Rb/sup +/ efflux, and /sup 45/Ca/sup + +/ net uptake were investigated. The insulinotropic effect of 16.7 mM glucose was decreased with the period of culturing during the first 14 days being significant after 2 days though in control experiments both protein content and ATP levels per islet were not affected and insulin content was only slightly decreased. Both NADPH and GSH decreased with time of culture. /sup 86/Rb/sup +/ efflux which is decreased by enhancing the glucose concentration from 3 to 5.6 mM in freshly isolated islets was not affected by culturing whatsoever, even not after 14 days of culture when there was not longer any insulin responsiveness to glucose. The /sup 45/Ca/sup + +/ net uptake was decreased during culturing. The data indicate (1) that the diminished glucose-stimulated release of insulin during culturing is not due to cell loss or simple energy disturbances, (2) that more likely it is the result of a diminished /sup 45/Ca/sup + +/ net uptake as a consequence of the inability of islet cells to maintain proper NADPH and GSH levels, and (3) that potassium (/sup 86/Rb/sup +/) efflux may not be related to changes of NADPH and GSH.

• Research Organization: Univ. of Tuebingen (West Germany)
• OSTI ID: 6945493
• Journal Information: Life Sci.; (United States), Journal Name: Life Sci.; (United States) Vol. 43:3; ISSN LIFSA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALDEHYDES
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BODY
CALCIUM 45
CALCIUM COMPOUNDS
CALCIUM ISOTOPES
CARBOHYDRATES
CATIONS
CELL CULTURES
CHARGED PARTICLES
COENZYMES
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DRUGS
ENDOCRINE GLANDS
EVEN-ODD NUCLEI
GLANDS
GLUCOSE
GLUTATHIONE
HEXOSES
HORMONES
INSULIN
INTERMEDIATE MASS NUCLEI
IONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MEMBRANE TRANSPORT
MINUTES LIVING RADIOISOTOPES
MONOSACCHARIDES
NADP
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANS
PANCREAS
PEPTIDE HORMONES
PEPTIDES
POLYPEPTIDES
POTASSIUM COMPOUNDS
PROTEINS
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
RATS
RODENTS
RUBIDIUM 86
RUBIDIUM ISOTOPES
SACCHARIDES
SECRETION
TRACER TECHNIQUES
VERTEBRATES