title: Five new insulin-producing cell lines with differing secretory properties.
abstract: Five cell lines have been derived from a rat transplantable islet cell tumour using two different methods. The lines differ in morphology and contain and release different amounts of insulin and glucagon (insulin content, 1-90 pmol/10(6) cells; insulin release, 6-250 pmol/10(6) cells per 24 h; glucagon content, less than 0.005-35 pmol/10(6) cells; glucagon release, less than 0.05-10 pmol/10(6) cells per 24 h). All the lines responded to the presence of the secretagogues leucine (20 mmol/l) plus theophylline (5 mmol/l) by increasing the rate of release of insulin approximately twofold. A high extracellular concentration of potassium (40 mmol/l) caused a three- to tenfold calcium-dependent increase in release of insulin and a parallel release of glucagon. Increasing the concentration of glucose from 2.8 to 16.7 mmol/l did not alter the rate of insulin release by any of the cell lines.
mesh_terms: D007516:Adenoma, Islet Cell / Q000378:metabolism* / Q000648:ultrastructure; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D005934:Glucagon / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007930:Leucine / Q000494:pharmacology; D008854:Microscopy, Electron; D008858:Microscopy, Phase-Contrast; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000648:ultrastructure; D011188:Potassium / Q000378:metabolism; D051381:Rats; D013806:Theophylline / Q000494:pharmacology
chemical_list: D007328:Insulin; D005934:Glucagon; D013806:Theophylline; D007930:Leucine; D005947:Glucose; D011188:Potassium; D002118:Calcium