VPT 311: General and Systemic Veterinary Pharmacology (2+1)

PHARMACOLOGICAL ACTIONS OF INSULIN

Pharmacological actions

• Insulin binds to specific cell membrane located receptors.
• This facilitates the entry of glucose, aminoacids and potassium ions into most cells.
• This reverses the hyperglycemia of diabetes mellitus by allowing excess glucose to become intracellular.
• Inside the cell, protein synthesis is increased and glucose is phosphorylated by ATP and hexokinase and is used to derive energy or for incorporation into glycogen.
• The storage of carbohydrate is further aided by the inhibition of the action of the enzymes of glycogenolysis.
• Protein synthesis is aided by the impairment of gluconeogenesis.
• Insulin also facilitates fat deposition and strongly inhibits lipolysis.  
• Actions of insulin include
  • Increased glucose uptake into muscle and fat
  • Increased glycogenesis
  • Decreased glycogenolysis
  • Decreased gluconeogenesis
  • Stimulation of growth (anabolic)
  • Decreased lipolysis
  • Decreased protein breakdown