Functional and metabolic characteristics of dissociated mouse pancreatic islet cells in suspension

Free islet cells in suspension were prepared by enzymatic dissociation of isolated pancreatic islets of adult mice. Microscopical examination revealed morphologically well preserved cells which appeared viable to more than 80% as determined by the trypan blue exclusion test. In comparison with whole islets, such cell preparations showed no responsiveness to glucose in terms of insulin release. On the other hand, rates of (pro)insulin biosynthesis, protein biosynthesis and glucose oxidation showed a dose-dependent increase in response to increasing glucose concentrations (1.6-30 mmol/l). These findings indicate that, in spite of a defect to the exocytotic insulin release system, free islet cells displayed a number of properties compatible with a well preserved viability, viz., the retention of glucose sensitive (pro)insulin biosynthesis and metabolism.