Measurement of urinary vanilmandelic acid and homovanillic
acids by high-performance liquid chromatography with electrochemical detection following extraction by ion-exchange and ion-moderated partition.
 Nonstandard abbreviations: TH, tyrosine hydroxylase; L-dopa, L-dihydroxyphenylalanine; B[H.sub.4], tetrahydrobiopterin; THD, tyrosine hydroxylase deficiency; CSF, cerebrospinal fluid; 5-HIAA, 5-hydroxyindoleacetic acid; HVA, homovanillic
acid; MHPG, 3-methoxy-4-hydroxy-phenylglycol; and VMA, vanillylmandelic acid.
acid (HVA) level in CSF was mildly elevated, at 80.9ng/ml (normal, <50ng/ml).
Chronic manganese overload stimulates monoamine oxidase activity, increasing dopaminergic degradation and accumulation of its metabolite, homovanillic
These antidepressant-like effects were associated with higher concentrations of norepinephrine and dopamine and their metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic
acid (HVA), respectively, in the hippocampus.
acid and 5-hydroxyindoleacetic acid cerebrospinal fluid levels: a study with and without probenecid administration of their relationship to the state of consciousness after head injury.
In this study, significant correlations were found between the phenylalanine (Phe) to tyrosine (Tyr) ratio and CSF concentrations of both dopamine and its metabolite, homovanillic
dioica methanolic leaf extract showed the presence of cinnamic acid, coumarins, and homovanillic
acid as phenolic compounds.
Four compounds (both caffeic acid hexosides (m/z 341), homovanillic
acid hexoside (m/z 343), and first dicaffeoylquinic acid isomer (m/z 515)) showed increasing trends, three compounds showed decreasing trends, and eight compounds had maximum levels at half-ripe stage.
This change was associated with increased levels of DA metabolites: homovanillic
acid in the prefrontal cortex and in the hippocampus, as well as 3,4-dihydroxyphenylacetic acid (DOPAC) in the prefrontal cortex .
DA, 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic
acid (HVA) were determined by the use of LC-MS/MS.
The neuroprotective assessment of echinacoside (9) showed that it prevents the 6-hydroxydopamine- (6-OHDA-) induced extracellular loss of monoamine neurotransmitters, such as 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic
acid in rat striatum .