This article needs to be updated. The reason given is: no files for 2006 are listed at the cited source, but files for 2013 are there; NLM releases this information annually. Please help update this article to reflect recent events or newly available information. (February 2020)

The following is a partial list of the "A" codes for Medical Subject Headings (MeSH), as defined by the United States National Library of Medicine (NLM).

This list continues the information at List of MeSH codes (A02). Codes following these are found at List of MeSH codes (A04). For other MeSH codes, see List of MeSH codes.

The source for this content is the set of 2006 MeSH Trees from the NLM.

MeSH  A03 – digestive system

MeSH  A03.159 – biliary tract

MeSH  A03.159.183 – bile ducts

• MeSH  A03.159.183.079 – extrahepatic bile ducts
  • MeSH  A03.159.183.079.300 – common bile duct
    • MeSH  A03.159.183.079.300.950 – Ampulla of Vater
      • MeSH  A03.159.183.079.300.950.600 – Sphincter of Oddi
  • MeSH  A03.159.183.079.450 – cystic duct
  • MeSH  A03.159.183.079.600 – common hepatic duct
• MeSH  A03.159.183.158 – intrahepatic bile ducts
  • MeSH  A03.159.183.158.125 – bile canaliculi

MeSH  A03.159.439 – gallbladder

MeSH  A03.556 – gastrointestinal tract

MeSH  A03.556.124 – intestines

• MeSH  A03.556.124.369 – intestinal mucosa
  • MeSH  A03.556.124.369.290 – enterocytes
  • MeSH  A03.556.124.369.320 – goblet cells
  • MeSH  A03.556.124.369.700 – paneth cells
• MeSH  A03.556.124.526 – large intestine
  • MeSH  A03.556.124.526.070 – anal canal
  • MeSH  A03.556.124.526.209 – cecum
    • MeSH  A03.556.124.526.209.290 – appendix
  • MeSH  A03.556.124.526.356 – colon
    • MeSH  A03.556.124.526.356.333 – ascending colon
    • MeSH  A03.556.124.526.356.500 – descending colon
    • MeSH  A03.556.124.526.356.668 – sigmoid colon
    • MeSH  A03.556.124.526.356.834 – transverse colon
  • MeSH  A03.556.124.526.767 – rectum
• MeSH  A03.556.124.684 – small intestine
  • MeSH  A03.556.124.684.124 – duodenum
    • MeSH  A03.556.124.684.124.236 – Ampulla of Vater
      • MeSH  A03.556.124.684.124.236.572 – Sphincter of Oddi
    • MeSH  A03.556.124.684.124.322 – Brunner Glands
  • MeSH  A03.556.124.684.249 – ileum
    • MeSH  A03.556.124.684.249.400 – ileocecal valve
    • MeSH  A03.556.124.684.249.612 – Meckel Diverticulum
  • MeSH  A03.556.124.684.500 – jejunum

MeSH  A03.556.249 – lower gastrointestinal tract

• MeSH  A03.556.249.124 – ileum
  • MeSH  A03.556.249.124.400 – ileocecal valve
  • MeSH  A03.556.249.124.612 – Meckel Diverticulum
• MeSH  A03.556.249.249 – large intestine
  • MeSH  A03.556.249.249.070 – anal canal
  • MeSH  A03.556.249.249.209 – cecum
    • MeSH  A03.556.249.249.209.290 – appendix
  • MeSH  A03.556.249.249.356 – colon
    • MeSH  A03.556.249.249.356.333 – ascending colon
    • MeSH  A03.556.249.249.356.500 – descending colon
    • MeSH  A03.556.249.249.356.668 – sigmoid colon
    • MeSH  A03.556.249.249.356.834 – transverse colon
  • MeSH  A03.556.249.249.767 – rectum
• MeSH  A03.556.249.750 – jejunum

MeSH  A03.556.500 – mouth

• MeSH  A03.556.500.379 – dentition
• MeSH  A03.556.500.760 – salivary glands
  • MeSH  A03.556.500.760.464 – parotid gland
  • MeSH  A03.556.500.760.640 – salivary ducts
  • MeSH  A03.556.500.760.650 – minor salivary glands
  • MeSH  A03.556.500.760.687 – sublingual gland
  • MeSH  A03.556.500.760.812 – submandibular gland
  • MeSH  A03.556.500.760.906 – von Ebner glands
• MeSH  A03.556.500.885 – tongue
  • MeSH  A03.556.500.885.431 – lingual frenum
  • MeSH  A03.556.500.885.779 – taste buds

MeSH  A03.556.750 – pharynx

MeSH  A03.556.875 – upper gastrointestinal tract

• MeSH  A03.556.875.249 – duodenum
  • MeSH  A03.556.875.249.160 – Ampulla of Vater
    • MeSH  A03.556.875.249.160.572 – Sphincter of Oddi
  • MeSH  A03.556.875.249.322 – Brunner Glands
• MeSH  A03.556.875.500 – esophagus
  • MeSH  A03.556.875.500.180 – esophageal mucosa
  • MeSH  A03.556.875.500.360 – upper esophageal sphincter
  • MeSH  A03.556.875.500.414 – esophagogastric junction
    • MeSH  A03.556.875.500.414.350 – lower esophageal sphincter
• MeSH  A03.556.875.875 – stomach
  • MeSH  A03.556.875.875.163 – cardia
  • MeSH  A03.556.875.875.330 – esophagogastric junction
    • MeSH  A03.556.875.875.330.350 – lower esophageal sphincter
  • MeSH  A03.556.875.875.419 – gastric fundus
  • MeSH  A03.556.875.875.440 – gastric mucosa
    • MeSH  A03.556.875.875.440.150 – gastric chief cells
    • MeSH  A03.556.875.875.440.250 – enterochromaffin cells
    • MeSH  A03.556.875.875.440.300 – gastrin-secreting cells
    • MeSH  A03.556.875.875.440.708 – gastric parietal cells
    • MeSH  A03.556.875.875.440.854 – somatostatin-secreting cells
  • MeSH  A03.556.875.875.578 – gastric stump
  • MeSH  A03.556.875.875.716 – pyloric antrum
  • MeSH  A03.556.875.875.799 – pylorus

MeSH  A03.620 – liver

MeSH  A03.620.150 – intrahepatic bile ducts

• MeSH  A03.620.150.125 – bile canaliculi

MeSH  A03.620.575 – round ligament of liver

MeSH  A03.734 – pancreas

MeSH  A03.734.414 – islets of langerhans

• MeSH  A03.734.414.065 – glucagon-secreting cells
• MeSH  A03.734.414.131 – insulin-secreting cells
• MeSH  A03.734.414.587 – pancreatic polypeptide-secreting cells
• MeSH  A03.734.414.793 – somatostatin-secreting cells

MeSH  A03.734.540 – exocrine pancreas

MeSH  A03.734.667 – pancreatic ducts

• MeSH  A03.734.667.500 – Ampulla of Vater

The list continues at List of MeSH codes (A04).