Rat brain monoamine metabolism and hypobaric hypoxia: a new approach.
A chromatographic method with electrochemical detection was used to measure noradrenaline (NA), dopamine (DA), and serotonin (5-HT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 3-methoxytyramine (3-MT) and 5-hydroxyindoleacetic acid (5-HIAA) in several brain areas (hypothalamus, hippocampus, striatum and rest of the brain) of rats exposed to a 7000 m simulated altitude for 3 hr. This new direct approach, not using a pharmacological tool, provides further information on the hypobaric hypoxia effects on the main DA and 5-HT metabolic steps. In the hypothalamus, a decreased NA level with increased DA and DOPAC contents was considered as the result of dopamine-beta-hydroxylase activity impairment. The decrease of both 5-HIAA and DOPAC in all brain areas provides further evidence of the hypoxia-induced decrement in MAO activity. Furthermore, in the striatum, it was shown that catechol-O-methyl transferase, up to now considered unaffected by hypoxia, may also be altered by oxygen deficiency.
D000818:Animals; D001679:Biogenic Amines / Q000378:metabolism*; D001921:Brain / Q000201:enzymology / Q000378:metabolism*; D001923:Brain Chemistry; D002394:Catechol O-Methyltransferase / Q000032:analysis; D004298:Dopamine / Q000378:metabolism; D004299:Dopamine beta-Hydroxylase / Q000032:analysis; D000860:Hypoxia / Q000378:metabolism*; D008297:Male; D008995:Monoamine Oxidase / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism
D001679:Biogenic Amines; D012701:Serotonin; D004299:Dopamine beta-Hydroxylase; D008995:Monoamine Oxidase; D002394:Catechol O-Methyltransferase; D004298:Dopamine