homovanillic acid

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ho·mo·va·nil·lic ac·id (HVA),

(hō'mō-vă-nil'ik as'id),
4-Hydroxy-3-methoxyphenylacetic acid; a phenol found in human urine; produced through the methylation of homoprotocatechuic acid on the meta-OH group. It is the principal urinary metabolite of dopa and dopamine.

homovanillic acid

/ho·mo·va·nil·lic ac·id/ (ho″mo-vah-nil´ik) a major terminal urinary metabolite, converted from dopa, dopamine, and norepinephrine.

homovanillic acid (HVA)

[hō′mōvənil′ik]
an acid that is produced by the normal metabolism of dopamine and that may occur at an elevated level in urine in association with tumors of the adrenal gland. Its normal accumulation in a 24-hour collection urine sample is 15 mg.

homovanillic acid

HVA Physiology A major dopamine metabolite used to synthesize epinephrine and norepinephrine and excreted in urine; HVA is usually measured with the major catecholamines and other catecholamine metabolites; HVA is ↑ in neuroblastoma and ganglioneuroma Ref range 0-15 mg/24 hr urine. See Hypertension, Pheochromocytoma.

ho·mo·va·nil·lic ac·id

(HVA) (hō'mō-vă-nil'ik as'id)
A phenol found in human urine; produced through the methylation of homoprotocatechuic acid on the meta-OH group.

ho·mo·va·nil·lic ac·id

(HVA) (hō'mō-vă-nil'ik as'id)
A phenol found in human urine.

homovanillic acid (hō´mōvənil´ik),

n an acid that is produced by normal metabolism of dopamine and may be elevated in the urine in association with tumors of the adrenal gland.
References in periodicals archive ?
subterminale & others) Figure 5 Neurotransmitter Metabolites Phenylalanine and Tyrosine Metabolites 33 Homovanillic (HVA) 0.
We used HPLC coupled with an electrochemical detector (for monoamines) or a fluorescent detector (for amino acids) to quantify dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), norepinephrine (NE), serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), glutamine (GLN), glutamate (GLU), and [gamma]-aminobutyric acid (GABA), expressed in nanograms per milligram protein.
This distance is shorter than the previously observed 5 carbon atoms, or 5A, as the shortest linker between 2 small haptens (histamine and homovanillic acid) that allowed a true sandwich formation for the linear synthetic molecule (16).
For example, in a sample of 22 adults with HIV (five participants were HIV seronegative, but at risk for HIV infection, whereas 11 were HIV seropositive without neurological disease; six had HIV-related neurological disease), Berger, Kumar, Kumar, Fernandez, and Levin (1994) found low levels of dopamine and homovanillic acid, a dopamine metabolite, in the cerebrospinal fluid.
Early studies found decreased levels of the dopamine metabolite homovanillic acid and the serotonin metabolite 5-HIAA in the cerebrospinal fluid of individuals with depression who died of suicide, suggesting decreased presynaptic function of dopamine and serotonin.
Ganglioneuroblastomas have a propensity for secreting catecholamines, and approximately 90-95% actively secretes vinylmandelic acid (VMA) and homovanillic acid (HVA).
As recent and extensive pharmacologic reviews have noted, studies have found increased plasma corticotropin and corticosteriod concentrations (rats), an inhibition of the reuptake of norepinephrine and decreased plasma levels of norepinephrine, luteinizing hormone and prolactin (humans), increases in homovanillic acid in depressed patients and an improvement in dopaminergic tone (26), (38).
Normal levels of homovanillic acid and vanillylmandelic acid support a diagnosis of PNET over neuroblastoma.
The levels of Dopamine (DA) and Homovanillic acid (HVA) in striatum were determined by Ultra-performance liquid chromatography combined with time-of-flight mass spectrometry (UPLC-ToF-MS).
1999), while higher MDMA levels reduce dopamine and homovanillic acid levels (Taffe et al.
The blood glucose level increases with increase in homovanillic acid (metabolite of dopamine) on fasting (36).
9] Homovanillic acid (HVA), vanillylmandelic acid (VMA) and acidic metabolites of catecholamines are excreted in higher than normal amounts by patients with neuroblastoma, and can therefore be used as tumour markers for diagnosis.