抄録
Kinetic analyses of glucose-induced insulin release from the perfused rat pancreas and the perifused rat islets were performed by Lineweaver-Burk's and Hill's equations. All dose-response curves tested here were sigmoid with Km values of 4-5 mM and 8-9mM glucose, respectively in a K+-depleted and the normal media in the perfusion system, and with a Km value of 8-9mM glucose under either a square-wave or a slow-rise stimulation in the perifusion system. Each Lineweaver-Burk plot was represented as a parabolic profile and therefore each insulin secretory response seem to be n reaction orders (n>1) for perfusion and the perifusion with the normal medium, except for the perfusion with the K+-depleted medium. All Hill plots for the rate of insulin release from the perfused pancreas and perifused islets under all experimental conditions were demonstrated as straight lines with various slopes.
Each kinetic constant, e.g., Km (Michaelis constant), K (equilibrium constant) and n (Hill's constant or reaction order) was calculated from Hill's equation applied to the insulin secretory response, and particularly each Km value was very similar to that described above. It was concluded that Hill's method seemed to beb available for the kinetic analysis of the rate of glucose-induced insulin release.
