TLS Online TPP Program

#Id: 6531

#Unit 7. System Physiology – Animal

Insulin secretion by the pancreatic beta cells in response to increased blood glucose concentration

TLS Online TPP Program

#Id: 6532

#Unit 7. System Physiology – Animal

The beta cells have a large number of glucose transporters that permit a rate of glucose influx that is proportional to the blood concentration in the physiological range

TLS Online TPP Program

#Id: 6533

#Unit 7. System Physiology – Animal

The entry of glucose into pancreatic β cells is mediated by the GLUT2 glucose transporter Because the Km for glucose of GLUT2 is 20 mM, a rise in extracellular glucose from 5 mM, causes a proportional increase in the rate of glucose entry

TLS Online TPP Program

#Id: 6534

#Unit 7. System Physiology – Animal

The conversion of glucose into pyruvate is accelerated, resulting in an increase in the concentration of ATP in the cytosol

TLS Online TPP Program

#Id: 6535

#Unit 7. System Physiology – Animal

The binding of ATP to  ATP sensitive K+ channels in the β cells closes the channels, reducing the efflux of K+ ions from the cell. The resulting small depolarization of the plasma membrane

TLS Online TPP Program

#Id: 6536

#Unit 7. System Physiology – Animal

Small depolarization of the plasma membrane triggers the opening of voltage- sensitive Ca2+ channels