Insulin Secretion Control

• 1 - normal blood glucose levels

  • K+ channels are open
  • potential difference of -70mv
• 2 - high blood glucose concentration causes glucose to move into cell through glucose channels
• 3 - glucose metabolised to form ATP
• 4 - the extra ATP binds to K+ channels and closes them
• 5 - as the K+ ions can no longer diffuse out, the potential difference reduces to -30mv

  • depolarisation
• 6 - voltage gated Ca2+ channels open, allowing ions to enter the cell
• 7 - secretory vesicles release insulin by exocytosis