Work

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

Year: 1989

Type: article

Abstract: 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 86Rb+ flux techniques. Both PMA and somatostatin hyperpolarize insulinoma cells by activating ATP-sensitive K+ 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 86Rb+ 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+ channels are discussed.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.86.8.2971

Authors: J R de Weille, H Schmid-Antomarchi, M Fosset, M Lazdunski

Institution: Centre National de la Recherche Scientifique

Language: English

Topic: Ion channel regulation and function

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: bronze

Funder: Centre National de la Recherche Scientifique