Nutrient induced insulin release from an insulinoma derived B-cell line.

The present study describes the effect of nutrient secretagogues upon insulin release from an insulinoma derived B-cell line RINm5F. Glucose failed to stimulate insulin release, it did however increase the rate of glucose oxidation by some 16 fold. Glyceraldehyde stimulated insulin release in a concentration dependent manner, maximum stimulation occurring at 20 mmol/l. The response to glyceraldehyde was suppressed by calcium channel blockade and calmodulin inhibition. Insulin release was also stimulated by the amino acids leucine and arginine, maximum stimulation for both amino acids occurring at 15 mmol/l. The present study confirms the usefulness of this cell line as a model for the study of insulin secretion.