title: Circadian rhythms in the central cholinergic system in aging animals.
mesh_terms: D000109:Acetylcholine / Q000097:blood; D000110:Acetylcholinesterase / Q000097:blood; D000375:Aging; D000818:Animals; D002795:Choline O-Acetyltransferase / Q000097:blood; D002799:Cholinergic Fibers / Q000502:physiology*; D002940:Circadian Rhythm; D008297:Male; D051381:Rats / Q000378:metabolism*
chemical_list: D002795:Choline O-Acetyltransferase; D000110:Acetylcholinesterase; D000109:Acetylcholine