Age-associated alteration of serotonergic synaptic neurochemistry in rat rostral hypothalamus.
Levels of monoamines and metabolites in rostral and caudal hypothalamic fragments of young (3-4 months) and old (25-26 months) Fischer 344-rats were compared. There were no differences between fragments of young animals. In senescent rats, 5-hydroxyindoleacetic acid (5HIAA) increased in both rostral and caudal hypothalamus. The ratio 5HIAA/5HT (serotonin), an index of serotonin turnover, increased only rostrally. This age-related increase of 5HIAA/5HT in rostral hypothalamus was associated with a decrease in [3H]-spiperone binding. There were no age-related changes of MAO-A activity in the hypothalamus or of serum tyrosine or tryptophan levels.
D L
DL
Sparks
W R
WR
Markesbery
J T
JT
Slevin
D000375:Aging; D000818:Animals; D002395:Catecholamines / Q000032:analysis; D006897:Hydroxyindoleacetic Acid / Q000032:analysis; D007031:Hypothalamus / Q000502:physiology*; D008995:Monoamine Oxidase / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D011985:Receptors, Serotonin / Q000032:analysis; D012701:Serotonin / Q000032:analysis / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission
D002395:Catecholamines; D011985:Receptors, Serotonin; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D008995:Monoamine Oxidase