Plasma Homovanillic Acid as a Predictor of Response to Neuroleptics

Subchronic Haloperidol Downregulates Dopamine Synthesis Capacity in the Brain of Schizophrenic Patients In Vivo

“…Concentrations of the DA metabolite homovanillic acid (HVA) measured in biological fluids have often served as an index of cerebral DA catabolism in humans. Thus, the baseline plasma HVA concentration and the initial increase occurring upon initiation of neuroleptic treatment both correlate with treatment response (Chang et al, 1988;Davila et al, 1988). Plasma HVA concentrations decrease with treatment in responders, whereas they are essentially unchanged in nonresponders (Bowers et al, 1984).…”

“…Plasma HVA concentrations decrease with treatment in responders, whereas they are essentially unchanged in nonresponders (Bowers et al, 1984). Patients with predominantly negative schizophrenic symptoms show a lower initial increase in HVA concentrations and a flat subsequent decrease (Davila et al, 1988). However, much of the plasma HVA is actually derived from the synthesis in catecholamines in sympathetic organs, and so is an imperfect index of central dopaminergic transmission (Amin et al, 1992).…”

Plasma Catecholamine Metabolites as Markers for Psychosis and Antipsychotic Response in Schizophrenia

“…20 , NO . 6 treatment that also parallels the decrease in psychosis (Davila et al 1988(Davila et al , 1995Duncan et al 1993), while others did not observe this effect (Pickar et al 1986). Other studies of antipsychotic efficacy have focused on response status as the outcome measure and have shown that plasma HVA decreases were significant only in responders (Davidson et al 1991a;Bowers et al 1984;Chang et al 1988;Van Putten et al 1989).…”

“…Interactions between the two systems have been well studied in the CSF and plasma of schizophrenic patients through their respective metabolites: the dopamine metabolite homovanillic acid (HVA) and the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG). Plasma HVA has been shown to reflect central or brain dopamine activity through studies in animals and humans (Bacopoulos et al 1979;Kendler et al 1982;Maas et al 1993;Lambert et al 1993;Amin et al 1992), indicating that 11-35% of plasma HVA comes from the brain.Several studies of schizophrenia have noted that the behavioral response to antipsychotic drugs (i.e., a decrease in psychosis levels) parallels a decrease in plasma HVA levels in schizophrenic patients over time (Pickar et al 1984(Pickar et al , 1986Davidson and Davis 1988;Davila et al 1988;Mazure et al 1991;Sharma et al 1989). Some studies have reported an initial increase in plasma HVA in the first week of antipsychotic drug From the VA Pittsburgh Healthcare System (MEK, JKY, DPvK), Pittsburgh, Pennsylvania; and Western Psychiatric Institute and Clinic (JKY, DPvK), University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania.…”

“…Several studies of schizophrenia have noted that the behavioral response to antipsychotic drugs (i.e., a decrease in psychosis levels) parallels a decrease in plasma HVA levels in schizophrenic patients over time (Pickar et al 1984(Pickar et al , 1986Davidson and Davis 1988;Davila et al 1988;Mazure et al 1991;Sharma et al 1989). Some studies have reported an initial increase in plasma HVA in the first week of antipsychotic drug From the VA Pittsburgh Healthcare System (MEK, JKY, DPvK), Pittsburgh, Pennsylvania; and Western Psychiatric Institute and Clinic (JKY, DPvK), University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania.…”