The development of an artificial beta cell system and its validation in depancreatized dogs: the physiological restoration of blood glucose homeostasis.
An instrument for the control of blood glucose in a closed-loop fashion has been developed. This artificial beta cell consists of 4 subunits: a Glucose Monitor, a Microcomputer, an Insulin Infusion Pump and a Printer. Its internal control algorithm was derived from the modeled dynamics of glucose-induced insulin secretion, and includes the effects of both the proportional and derivative actions of blood glucose concentration, and is expressed as: IIR = Kp . BG + Kd . deltaBG + Kc, where IIR is insulin infusion rate, BG and deltaBG are blood glucose concentration and rate of change in glycemia, respectively. Kp and Kd are individual coefficients and Kc is a constant of basal insulin secretion. The performance of this system was studied with various kinds of glucose challenges on anaesthetized depancreatized dogs. Its notable characteristics were: 1) the insulin infusion rate was such as to maintain physiological insulin levels, and 2) dextrose or glucagon infusions were not required.
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D003201:Computers; D003920:Diabetes Mellitus / Q000188:drug therapy / Q000378:metabolism*; D004285:Dogs; D005951:Glucose Tolerance Test; D006706:Homeostasis; D007261:Infusions, Intra-Arterial; D007328:Insulin / Q000008:administration & dosage; D007662:Ketosis / Q000188:drug therapy; D008991:Monitoring, Physiologic / Q000295:instrumentation*
D001786:Blood Glucose; D007328:Insulin