Pancreas / Glucose control

Pancreas anatomy

 

Pancreas

  • Mixed endocrine / exocrine gland
  • Secretes 1-1.5l pancreatic juice daily

 

Function of the pancreas

  1. Endocrine
    • Alpha cells: Glucagon
    • Beta Cells: Insulin
      1. Carbs: - Increase glucose uptake, stimulates glycogensis
      2. Proteins: Enhances AA into peripheral tissues, stimulates protein synthesis
      3. Fats: Stimulates lipid uptake
      4. Potassium: into cells
    • [Gamma cells: pancreatic polypeptide - reduces appetite]
    • Delta Cells: Somatostatin
  2. Exocrine
    • 1 - 1.5l pancreatic juice / day
    • Aqueous component - water, bicarbonate
    • Enzymatic component - digestive enzymes
      1. (1) Proteases (secreted as inactive zymogen form) - trypsinogen, chymotrypsinogen, procarboxypeptidase, proelastase
      2. (2) Lipolytic - Lipase, Phospholipase A2
      3. (3) Starch digestion - Amylase

Glucose metabolism

  • Sources
  1. Diet
  2. Glycogenolysis
  3. Gluconeogenesis
    • Lactate, glycerol, Amino acids

  • Blood sugar control
  1. Increase BM: Catecholamines, Glucocorticoids, Somatotrophin
  2. Decrease BM: Insulin

Ketosis

  1. Starvation
    • Diabetes - (omission of insulin, infection, drug induced)
    • Improper utilisation of TCA components
  2. Increased lipolysis and increased FFA production (readily transportable fatty acids that can be utilised by organs such as heart and brain)
  3. Ketone production - acetone, acetoacetate, B-hydroxybutyrate