Calcium and pancreatic beta-cell function. 5. Mobilisation of a glucose-stimulated pool of intracellular 45Ca by metabolic inhibitors and the ionophore A-23187. 1979

B Hellman

Glucose is believed to stimulate incorporation of calcium into the secretory granules of the pancreatic beta-cells. The mechanism of the glucose-stimulated accumulation of calcium in the granule pool was evaluated by measuring fluxes of 45Ca in beta-cell-rich pancreatic islets microdissected from ob/ob-mice. The incorporation of lanthanum-nondisplaceable 45Ca in response to phosphate in being suppressed by 10 micrometer antimycin A, 0.3 mM 2,4-dinitrophenol or 1 mM N-ethylmaleimide. Exposure to each of these metabolic inhibitors also resulted in a protracted efflux of the glucose-sensitive 45Ca under conditions when neither the 45Ca incorporated in the presence of 3 mM glucose nor in response to phosphate was significantly affected. The glucose-stimulated intracellular 45Ca existed in a state allowing it to be washed out with the ionophore A-23187. The results suggest that the glucose-stimulated incorporation of calcium into the secretory granules is mediated by transport against a concentration gradient into the granule sac.

UI MeSH Term Description Entries
D007515 Islets of Langerhans Irregular microscopic structures consisting of cords of endocrine cells that are scattered throughout the PANCREAS among the exocrine acini. Each islet is surrounded by connective tissue fibers and penetrated by a network of capillaries. There are four major cell types. The most abundant beta cells (50-80%) secrete INSULIN. Alpha cells (5-20%) secrete GLUCAGON. PP cells (10-35%) secrete PANCREATIC POLYPEPTIDE. Delta cells (~5%) secrete SOMATOSTATIN. Islands of Langerhans,Islet Cells,Nesidioblasts,Pancreas, Endocrine,Pancreatic Islets,Cell, Islet,Cells, Islet,Endocrine Pancreas,Islet Cell,Islet, Pancreatic,Islets, Pancreatic,Langerhans Islands,Langerhans Islets,Nesidioblast,Pancreatic Islet
D002118 Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D003594 Cytoplasmic Granules Condensed areas of cellular material that may be bounded by a membrane. Cytoplasmic Granule,Granule, Cytoplasmic,Granules, Cytoplasmic
D004140 Dinitrophenols Organic compounds that contain two nitro groups attached to a phenol.
D005033 Ethylmaleimide A sulfhydryl reagent that is widely used in experimental biochemical studies. N-Ethylmaleimide,N Ethylmaleimide
D005947 Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Dextrose,Anhydrous Dextrose,D-Glucose,Glucose Monohydrate,Glucose, (DL)-Isomer,Glucose, (alpha-D)-Isomer,Glucose, (beta-D)-Isomer,D Glucose,Dextrose, Anhydrous,Monohydrate, Glucose
D000001 Calcimycin An ionophorous, polyether antibiotic from Streptomyces chartreusensis. It binds and transports CALCIUM and other divalent cations across membranes and uncouples oxidative phosphorylation while inhibiting ATPase of rat liver mitochondria. The substance is used mostly as a biochemical tool to study the role of divalent cations in various biological systems. 4-Benzoxazolecarboxylic acid, 5-(methylamino)-2-((3,9,11-trimethyl-8-(1-methyl-2-oxo-2-(1H-pyrrol-2-yl)ethyl)-1,7-dioxaspiro(5.5)undec-2-yl)methyl)-, (6S-(6alpha(2S*,3S*),8beta(R*),9beta,11alpha))-,A-23187,A23187,Antibiotic A23187,A 23187,A23187, Antibiotic
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D000900 Anti-Bacterial Agents Substances that inhibit the growth or reproduction of BACTERIA. Anti-Bacterial Agent,Anti-Bacterial Compound,Anti-Mycobacterial Agent,Antibacterial Agent,Antibiotics,Antimycobacterial Agent,Bacteriocidal Agent,Bacteriocide,Anti-Bacterial Compounds,Anti-Mycobacterial Agents,Antibacterial Agents,Antibiotic,Antimycobacterial Agents,Bacteriocidal Agents,Bacteriocides,Agent, Anti-Bacterial,Agent, Anti-Mycobacterial,Agent, Antibacterial,Agent, Antimycobacterial,Agent, Bacteriocidal,Agents, Anti-Bacterial,Agents, Anti-Mycobacterial,Agents, Antibacterial,Agents, Antimycobacterial,Agents, Bacteriocidal,Anti Bacterial Agent,Anti Bacterial Agents,Anti Bacterial Compound,Anti Bacterial Compounds,Anti Mycobacterial Agent,Anti Mycobacterial Agents,Compound, Anti-Bacterial,Compounds, Anti-Bacterial
D000968 Antimycin A An antibiotic substance produced by Streptomyces species. It inhibits mitochondrial respiration and may deplete cellular levels of ATP. Antimycin A1 has been used as a fungicide, insecticide, and miticide. (From Merck Index, 12th ed) Butanoic acid, 2(or 3)-methyl-, 3-((3-(formylamino)-2-hydroxybenzoyl)amino)-8-hexyl-2,6-dimethyl-4,9-dioxo-1,5-dioxonan-7-yl ester,Antimycin A1

Related Publications

B Hellman
December 1976, European journal of pharmacology,
B Hellman
October 1984, Nihon Ika Daigaku zasshi,
B Hellman
November 1983, The American journal of physiology,
Copied contents to your clipboard!