Pancreas - endocrine

By volume

• 2% - Islets of Langerhans
  * 1-2 million islets
• 80% - exocrine pancreas
• Rest - ducts and blood vessels

Cell types

• A cells - glucagon
  * 20% of islet cells
• B cells - insulin
  * 60-70% of islet cells
• D cells - somatostatin
• F cells - pancreatic polypeptide.