Mathematical Modeling of Interacting Glucose-Sensing Mechanisms and Electrical Activity Underlying Glucagon-Like Peptide 1 Secretion
Fig 4
Simulated electrical activity in primary L-cells.
A: simulation of electrical activity triggered by SGLT1-substrate uptake, corresponding to αMG application, in primary L-cells with default parameters and extracellular SGLT1-substrate, GSGLT1, changing from 0.1 mM to 1 mM and 20 mM as indicated. B: SGLT1-associated current (left axis) and average calcium current (red, right axis) corresponding to the simulation in panel A. C: Simulation of electrical activity triggered by the K(ATP)-channel blocker tolbutamide. Default parameters and K(ATP)-channel conductance, gK(ATP), changing from from 3 pS/pF to 0 pS/pF. Grey bars indicate application of the substances. D: Voltage peak as a function of GSGLT1 and gK(ATP). E: Spiking frequency as a function of GSGLT1 and gK(ATP). In panels D and E, the black arrows indicate the parameter changes in panels A, B and C. The red arrow indicates the effect of an increase in intracellular glucose concentration due to GLUT2 transport.