Spontaneous acetylcholine release in the hippocampus exhibits a diurnal variation in both young and old rats.
Extracellular levels of acetylcholine (ACh) in the hippocampus were measured by the microdialysis method in freely moving young (3-4 months old) and old (18-24 months old) female rats over a period of 24 h to examine the effect of aging on hippocampal ACh release. Hippocampal ACh release during a 24-h period exhibited a diurnal variation with higher levels during the dark cycle than during the light cycle in old rats as well as young rats. The present study suggests that a diurnal variation in ACh release is maintained fairly well until the rats are at least 24 months old.
Mizuno
T
T
Department of Physiology, Yokohama City University School of Medicine, Japan.
Arita
J
J
Kimura
F
F
D000109:Acetylcholine / Q000378:metabolism*; D000375:Aging / Q000502:physiology*; D000818:Animals; D002940:Circadian Rhythm; D005260:Female; D006624:Hippocampus / Q000378:metabolism*; D017551:Microdialysis; D009043:Motor Activity / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar
D000109:Acetylcholine