Abstract

A novel insulin-secreting cell line, BRIN-BD11, was recently established following electrofusion of RINm5F cells with NEDH rat pancreatic islet cells. In the present study, D-glucose metabolism was compared in BRIN-BD11 and RINm5F cells. The concentration dependency of D-[5-H-3]glucose utilization displayed a comparable pattern in the two cell lines, but the absolute values were lower in BRIN-BD11 than RINm5F cells. Except in the case of D-[1-C-14]glucose, the ratio between C-14 labeled D-glucose oxidation and D-[5-H-3]glucose utilization was higher, however, in BRIN-BD11 than RINm5F cells. Moreover, BRIN-BD11 cells were less affected than RINm5F cells by a rise in D-glucose concentration, in terms of the inhibitory action of the hexose upon oxidative variables, such as oxidative glycolysis, pyruvate decarboxylation, and oxidation of glucose-derived acetyl residues in the Krebs cycle. The total energy yield from D-glucose catabolism appeared similar, however, in BRIN-BD11 and RINm5F cells. These findings extend the knowledge that BRIN-BD11 cells display an improved metabolic and secretory behavior, when considering the difference otherwise found between normal and tumoral islet cells. (C) 1996 Academic Press, Inc.