Regulation of ATP-sensitive K sup + channels in insulinoma cells: Activation by somatostatin and protein kinase C and the role of cAMP

Journal Article · Fri Mar 31 23:00:00 EST 1989 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.86.8.2971· OSTI ID:5300376

De Weille, J R; Schmid-Antomarchi, H; Fosset, M; Lazdunski, M ^[1]

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1. Centre de Biochimie du Centre National de la Recherche Scientifique, Nice (France)

The actions of somatostatin and of the phorbol ester 4{beta}-phorbol 12-myristate 13-acetate (PMA) were studied in rat insulinoma (RINm5F) cells by electrophysiological and {sup 86}Rb{sup +} flux techniques. Both PMA and somatostatin hyperpolarize insulinoma cells by activating ATP-sensitive K{sup +} channels. The presence of intracellular GTP is required for the somatostatin effects. PMA- and somatostatin-induced hyperpolarization and channel activity are inhibited by the sulfonylurea glibenclamide. Glibenclamide-sensitive {sup 86}Rb{sup +} efflux from insulinoma cells is stimulated by somatostatin in a dose-dependent manner (half maximal effect at 0.7 nM) and abolished by pertussis toxin pretreatment. Mutual roles of a GTP-binding protein, of protein kinase C, and of cAMP in the regulation of ATP-sensitive K{sup +} channels are discussed.

• OSTI ID: 5300376
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (USA) Vol. 86:8; ISSN 0027-8424; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
AMP
ANIMAL CELLS
ANIMALS
ATP
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
CARCINOGENS
DAYS LIVING RADIOISOTOPES
ENZYMES
ESTERS
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAMMALS
MEMBRANE TRANSPORT
MINUTES LIVING RADIOISOTOPES
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PHORBOL ESTERS
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
PHYSIOLOGY
POTASSIUM COMPOUNDS
RADIOISOTOPES
RATS
RODENTS
RUBIDIUM 86
RUBIDIUM ISOTOPES
SOMATOSTATIN
TRANSFERASES
TUMOR CELLS
UPTAKE
VERTEBRATES