title: Glucagon storage, release and degradation by tumoral islet cells (RINm5F line).
abstract: Tumoral islet cells of the RINm5F line contain and release glucagon. Over 90 min incubation, the secreted hormone represents about 50% of the final cell content (1.4 +/- 03 fg/cell). L-arginine augments modestly glucagon release, the relative magnitude of such an effect being inversely related to the concentration of D-glucose. The immunoreactive material secreted by the cells consists of both true glucagon (59-64%) and larger peptides. The RINm5F cells also release a proteolytic factor able to degrade exogenous glucagon or insulin. These results reveal that glucagon producing tumoral cells display several abnormal features in their secretory behaviour.
authors.affiliation: Fundacion Jimenez Diaz, Centro Asociado al Consejo Superior de Investigaciones Cientificas, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Barreto
authors.forename: I
authors.initials: I
authors.lastname: Valverde
authors.forename: W J
authors.initials: WJ
authors.lastname: Malaisse
mesh_terms: D007516:Adenoma, Islet Cell / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D005934:Glucagon / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000378:metabolism*
chemical_list: D005934:Glucagon; D010447:Peptide Hydrolases