Alpha Cells

• Blood glucose falls below normal level, alpha-cells detect change and secrete glucagon into blood.

  Glucagon is complementary to receptors on target cell membranes- liver, muscles and adipose tissue.

  This leads to the activation of enzymes that:

  • Convert glycogen to glucose - glycogenolysis
  • Convert amino acids/ glycerol to glucose - gluconeogenesis
• The effect of glycogenesis and gluconeogenesis is to return glucose to the blood and return concentration to optimum. As a result alpha-cells are not stimulated, so glucagon secretion is reduced- negative feedback.