four major pancreatic endocrine cells , immunolocalized with the light and electron microscope , have been described : glucagon-containing cells ( granules of 440 nm in diameter ) , insulin cells ( 400 nm ) , somatostatin cells ( 610 nm ) , and pancreatic polypeptide-containing cells ( 460 nm ) .
C0022131
pancreatic endocrine
C0030280
glucagon