Release and Production of Insulin by Isolated, Perifused Rat Pancreatic Islets: Control by Glucose

Rat pancreatic islets, isolated from the whole gland by digestion with collagenase, were incubated in a continuous flow system in which various concentrations of glucose were contained in the buffer solution. The pattern of release of immunoreactive insulin (IRI) consisted generally of successive main phases with multiple minor fluctuations within the broader cyclic release. Threshold and responsiveness of various phases of IRI release with different glucose concentrations and flow rates have been investigated.