title: Aging and neurotransmitter systems.
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D001921:Brain / Q000201:enzymology; D002395:Catecholamines / Q000378:metabolism; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D003704:Dementia / Q000201:enzymology; D005968:Glutamate Decarboxylase / Q000378:metabolism; D006801:Humans; D008875:Middle Aged; D009474:Neurons / Q000201:enzymology; D018377:Neurotransmitter Agents / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D002395:Catecholamines; D018377:Neurotransmitter Agents; D005680:gamma-Aminobutyric Acid; D002795:Choline O-Acetyltransferase; D005968:Glutamate Decarboxylase