INCUBATION STUDIES OF PANCREAS FOR EVALUATION OF INSULIN ANALOGUES IN MAN, USING GEL CHROMATOGRAPHIC PROCEDURES
Human pancreas was taken from three patients, one was a patient with esophageal cancer, two with gastric cancer as surgical specimen. The incubation medium and incubated pancreas were gel chromato graphed on the Bio-Gel P-30 column after extraction with acid-ethanol. Each of fraction was assayed for immunoreactive insulin, C-peptide immunoreactivity and glucagon immunoreactivity. Two peaks of insulin were detected in the incubation medium and the incubated pancreas at the position of 6000 molecular weight region. The pancreatic tissue abounded in intermediate molecular size of insulin derivatives, but the secreted insulin was eluated only at the position of 6000 molecular weight region. Therefore the secretion mechanism of insulin might be selective. These findings suggest that the two groups of insulin could be directly secreted from human pancreas with the selective mechanism.