5-Hydroxyindoleacetic acid (5 HIAA) and homovanillic acid (HVA) following probenecid in acute psychotic patients treated with phenothiazines

Lumbar CSF 5 HIAA and HVA were measured following probenecid administration in acute psychotic patients before and during treatment with phenothiazines. Patients with more classical schizophrenic symptoms had higher values for 5 HIAA/HVA than other psychotics, depressives, and inmate volunteers. Prior to treatment CSF 5 HIAA, but not HVA, correlated significantly with several clinical items related to psychotic disorganization. Phenothiazine treatment produced significant increases in CSF HVA which could not be correlated with the dose of antipsychotic or antiparkinson drugs.     

5-Hydroxyindole acetic acid and homovanillic acid in cerebrospinal fluid in manic-depressive psychosis and the effect of probenecid treatment

Summary The increased concentrations of 5-hydroxyindole acetic acid and homovanillic acid produced in cerebrospinal fluid by probenecid has been investigated in 15 manic-depressive patients and 21 psychiatric control patients, and has been related to the concentrations of probenecid in the CSF. The pharmacokinetics of probenecid were the same in the manic-depressive patients and the controls, as judged by its concentrations in plasma (bound and free) and CSF after a standard oral dose p.o., and by measurements of half-life and volume of distribution after intravenous injection. — The manic-depressive patients had lower concentrations of 5-HIAA and HVA than controls at similar CSF concentrations of probenecid; this was concluded from results with pairs of patients matched with regard to probenecid in CSF, and from differences between the patients and controls in the slopes of the regression lines for probenecid in CSF against 5-HIAA/HVA. The differences in 5-HIAA/HVA between the diagnostic groups were greater with increasing concentrations of probenecid in CSF; and, with concentrations of probenecid in CSF>1.0 µg/ml, by using the 5HIAA concentrations it was possible to classify the patients correctly into their diagnostic groups in 92% of cases.     

5-hydroxyindoleacetic acid (and homovanillic acid) levels in the cerebrospinal fluid after probenecid application in patiens with manic-depressive psychosis

Summary Probenecid was administered to 17 depressed, 19 manic and 15 control patients and further to 11 healthy volunteers. Before and after the administration the levels of 5-hydroxyindoleacetic acid (5-HIAA) were determined in cerebrospinal fluid (CSF). In six of the depressed, seven of the manic and seven of the patients from the group of controls and volunteers also homovanillic acid (HVA) was determined in CSF. After the application of probenecid there is a significant increase in 5-HIAA and HVA in the control patients and healthy volunteers but not in the depressed and manic patients. No increase in HVA occurred in the depressed patients but in the manic ones the HVA values were almost as high as in the group of controls and healthy volunteers. It is suggested that the lack of increase in 5-HIAA and HVA after probenecid indicates an inhibition of the synthesis of the acids and thus of the corresponding amines (5-hydroxytryptamine and dopamine) in the brain.     

Effect of ECT and imipramine treatment on the concentration of 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid (HVA) in the cerebrospinal fluid of depressed patients

The influence of probenecid administration on 5HIAA and HVA concentrations in the CSF of depressed patients, was studied before and after treatment with imipramine or ECT.The average increase of the two metabolites in the CSF after probenecid was similar in the untreated depressed patients and in the same patients improved after both imipramine or ECT treatment.The treatment determined a significant increase in the CSF concentration of the acid metabolites also before the probenecid administration.     

Probenecid: Dosage,levels in plasma and cerebrospinal fluid (CSF) and influence upon CSF levels of homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in the rabbit

Probenecid retards the efflux of acid monoamine metabolites from the brain tissue and CSF to the blood. The probenecid-induced accumulation of these metabolites is held to be indicative of the turnover rate of the corresponding amines. Although the penetration of probenecid into the CSF does not proceed at a constant rate, Korf et al. (1972) and Sjöstrom (1972) have shown a correlation between CSF levels of probenecid and that of HVA and 5-HIAA. In this study an attempt was made to establish the relationship between doses of probenecid and levels of this compound in plasma and CSF; between levels in plasma and CSF; and between CSF levels of probenecid and of HVA and 5-HIAA. This study was performed in a homogeneous group of laboratory rabbits.All correlations proved to be significant. The implications of these results for studies using the probenecid technique are discussed.     

The dopamine-serotonin relationship in clozapine response

The effects of clozapine on the dopamine and serotonin systems may underlie its atypical pharmacologic and clinical profile. To examine this hypothesis, we measured dopamine and serotonin plasma and cerebrospinal (CSF) metabolites and the relationship of these values to treatment response in 19 neuroleptic refractory and intolerant schizophrenic patients. Only a small change in the CSF and plasma homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5HIAA) levels was found. However, the pretreatment CSF HVA/5HIAA ratio and, to a lesser extent, the CSF HVA level predicted treatment response. These results suggest that the modest relationship between HVA and 5-HIAA and treatment response supports the involvement of both neurotransmitters in the pathophysiology of schizophrenia.     

Gradients of concentrations of tryptophan and 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF).

CSF from neurological and other patients was analyzed for its content of tryptophan, 5-HIAA and homovanilic acid (HVA). The gradients of concentration of these substances from ventricular spaces to lumbar sac indicate that tryptophan and 5-HIAA probably enter the CSF from all levels of the nervous system, but that HVA originates entirely in the brain. A study of CSF tryptophan in patients with hepatic cirrhosis provided no support for theories which implicate abnormal tryptophan metabolism as a cause of hepatic coma.     

Reduced cerebrospinal HVA concentrations and HVA/5-HIAA ratios in suicide attempters. Monoamine metabolites in 120 suicide attempters and 47 controls.

Dysfunctions of central monoaminergic systems are important elements of the leading biological hypotheses of suicide and depression. The purpose of the present paper was to study the levels and the relationships between the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), the dopamine metabolite homovanillic acid (HVA) and the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in the cerebrospinal fluid (CSF) in 120 hospitalised suicide attempters and 47 controls (healthy volunteers or patients admitted for minor surgery). The suicide attempters showed significantly lower HVA levels (174+/-82 vs. 216+/-96 nmol/L, P=0.004), HVA/5HIAA ratios (1.6+/-0.5 vs. 2.1+/-0.6, P=0.0001) and HVA/MHPG ratios (4.2+/-2.1 vs. 4.8+/-1.7, P=0.02) than the controls. The correlations between the monoamine metabolites were markedly lower in patients than in controls. CSF 5-HIAA showed no significant differences between patients and controls (107+/-40 vs. 108+/-51 nmol/L) or between violent and non-violent attempters (112+/-58 vs. 105+/-33 nmol/L). The monoamine metabolites showed no significant differences between survivors and patients who subsequently completed suicide, or between suicide attempters subgrouped by psychiatric diagnoses. The results suggest that low HVA levels and altered relationships between the monoamine metabolites are associated with suicidal behaviour.     

Influence of convulsive therapy on 5-hydroxyindoleacetic acid and homovanillic acid in cerebrospinal fluid in endogenous depression

The cerebrospinal fluid (CSF) levels of 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) were determined in 20 patients with endogenous depression before and 2–6 days after a full course of convulsive therapy, the depressive symptoms being simultaneously rated.

1. The level of 5-HIAA was similar to that in previous series of healthy controls while the level of HVA appeared somewhat low.
2. The levels did not change after therapy in spite of considerable clinical improvement.
3. There was no relation between the levels and the severity of the depressive state, nor between changes of the levels and degree of clinical improvement.
4. There was no relation between the levels and the severity of the depressive state, nor between changes of the levels and degree of clinical improvement.

The validity of determination of acid monoamine metabolites in CSF relative to the cerebral turn-over of the amines may be increased, if the elimination of metabolites from CSF is blocked with probenecid.     

CSF 5-HIAA as a predictor of treatment response in trichotillomania.

Trichotillomania is characterized by chronic hair-pulling resulting in noticeable hair loss. In a preliminary study, cerebrospinal fluid (CSF) measures in 8 medication-free, female, trichotillomania patients were compared to those of matched, normal controls. There was no difference between patients and controls in measures of CSF cortisol, 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and 3-methoxy-4-hydroxyphenylglycol (MHPG). CSF measures did not correlate with measures of trichotillomania symptomatology. However, degree of response to treatment with serotonin re-uptake inhibitors significantly correlated with baseline CSF 5-HIAA. This suggests that central serotonin turnover is specifically relevant to treatment response to serotonin re-uptake inhibitors in trichotillomania.     

Dystrobrevin-binding protein 1 gene (DTNBP1) variants associated with cerebrospinal fluid homovanillic acid and 5-hydroxyindoleacetic acid concentrations in healthy volunteers

The dystrobrevin binding protein-1 (DTNBP1) gene encodes dysbindin-1, a protein involved in neurodevelopmental and neurochemical processes related mainly to the monoamine dopamine. We investigated possible associations between eleven DTNBP1 polymorphisms and cerebrospinal fluid (CSF) concentrations of the major dopamine metabolite homovanillic acid (HVA), the major serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), and the major noradrenaline metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in healthy human subjects (n = 132). Two polymorphisms, rs2619538 and rs760666, were nominally associated with CSF HVA and 5-HIAA concentrations, whereas a third polymorphism, rs909706, showed association only with HVA. After correction for multiple testing only the associations between rs2619538 and HVA and 5-HIAA concentrations remained significant. No significant association was found between any of the investigated DTNBP1 polymorphisms and CSF MHPG concentrations. The results suggest that genetic variation in DTNBP1 gene affects the regulation of dopamine and serotonin turnover in the central nervous system of healthy volunteers.     

Individual differences in basal cisternal cerebrospinal fluid 5-HIAA and HVA in monkeys. The effects of gender, age, physical characteristics, and matrilineal influences.

We examined the effects of gender, age, weight, length, body shape (ectomorphy), and matrilineal influences on cisternal cerebrospinal fluid 5-hydroxyindoleacetic acid (CSF 5-HIAA) and homovanillic acid (HVA) in 78 socially living adult and adolescent vervet monkeys. CSF 5-HIAA and the 5-HIAA:HVA ratio were higher (by 27% and 18%, respectively) in females. In both sexes, CSF 5-HIAA and the 5-HIAA:HVA ratio increased with age. Neither weight nor length were independently related to CSF 5-HIAA or HVA; however, shape correlated with CSF 5-HIAA and HVA in males (higher in thin, long subjects). Male offspring had CSF 5-HIAA concentrations and 5-HIAA:HVA ratios that were significantly closer to their mothers than did age-matched, maternally unrelated males. Repeated measures of CSF 5-HIAA and HVA in another 22 males living in unvarying settings showed that individual differences in these measures persisted over time. The data underscore the impact of gender, age, and matrilineal relationships on individual differences in CSF monoamine metabolites and highlight the importance of controlling for age and gender in neuropharmacological investigations of clinical populations.     

Determinations of 5-hydroxyindoleacetic acid and homovanillic acid in human CSF with monitoring of probenecid levels in CSF and plasma

The accumulation of 5-HIAA and HVA in cerebrospinal fluid (CSF) was studied in eight healthy volunteers after oral administration of probenecid. Simulation indicated that a dose of 4.5 g probenecid should be used to achieve probenecid plasma concentrations between 200 and 400 g/ml. Almost complete inhibition of the active transport of the acidic metabolites was assumed to be obtained at these concentrations. Probenecid 4.5 g was administered in two doses (2.5 g and 2 g), separated by 4 h. Plasma samples were drawn at varying intervals over a period of 46 h and lumbar puncture (LP) was performed at either 14 h or 20 h after the first administration of probenecid. The concentration of probenecid, 5-HIAA and HVA in CSF was estimated and the probenecid-induced accumulation of 5-HIAA and HVA was compared with their baseline values. There were no statistically significant differences (P>0.05) in the accumulation of the monoamine metabolites between the two LP (14 h and 20 h), neither were there any differences in CSF concentrations of probenecid at the time of LP. There were only small differences in probenecid plasma concentrations, although statistically significant. Due to maximum blockade of the active transport system no correlation was observed between the CSF concentration of probenecid and the induced accumulation of 5-HIAA and HVA, respectively. The range of probenecid-induced accumulation for 5-HIAA and HVA in these volunteers was 156–429% and 183–600%, respectively. The suggested monitoring of probenecid plasma levels is proposed as a suitable model to investigate central neuronal activity of dopamine and serotonin in the central nervous system.     

Effects of tiapride on homovanillic acid levels in human cerebrospinal fluid drawn at pneumoencephalography

The effect of tiapride on HVA and 5-HIAA levels in the CSF drawn at pneumoencephalography (PEG) was studied. Five consecutive 5 ml fractions of CSF were drawn from control and tiapride-treated subjects. In both groups, a linear increase in HVA concentrations was found between the first and subsequent fractions. On the contrary, no significant difference in 5-HIAA concentrations was found in sequential CSF samples. Tiapride increased the mean HVA concentrations and caused a steeper caudocranial gradient of this metabolite but failed to modify 5-HIAA concentrations. The results suggest that tiapride blocks dopamine (DA) receptors and increases DA synthesis.     

Cerebrospinal fluid monoaminergic metabolites differ in wild anubis and hybrid (Anubis hamadryas) baboons: possible relationships to life history and behavior.

The article reports monoaminergic metabolite [homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylglycol (MHPG)], values from the cerebrospinal fluid (CSF) of 27 wild baboons (Papio hamadryas) aged 40 to 140 months. Animals were either anubis, or anubis with hamadryas admixture; males of the latter subspecies generally have a reduced tendency to disperse from their natal groups. Overall, the values and interrelationships among the CSF monoamine metabolites resembled data reported from closely related, captive-housed animals. For example, age was significantly correlated with HVA concentrations (r = -60, p < .05), but not with the other metabolites. Notably, males characterized by hamadryas admixture had significantly higher concentrations of HVA, 5-HIAA, and MHPG (p < .05, respectively), a result possibly driven by differences in serotonergic activity. These data provide initial evidence that variation in central monoaminergic activity, as indicated by CSF monoamine metabolite concentrations, may reflect differences in behavior and life history that have taxonomic and, perhaps, evolutionary significance.     

The effect of olanzapine treatment on monoamine metabolite concentrations in the cerebrospinal fluid of schizophrenic patients.

The mechanism of action of both typical antipsychotics and the atypical antipsychotic, clozapine, may be related to the (changing) interaction of dopamine and serotonin in schizophrenia. This study examined the effect of olanzapine in schizophrenic patients on cerebrospinal fluid (CSF) metabolites of dopamine (homovanillic acid, HVA) and serotonin (5-hydroxyindoleacetic acid, 5-HIAA). Twenty-three male schizophrenic patients, who were drug-free for at least 2 weeks (mean drug-free period of 35 days +/- 43; median 16 days), underwent a lumbar puncture (LP). Patients were subsequently treated with olanzapine 10 mg/day for 6 weeks, after which the LP was repeated. CSF was assayed for HVA and 5-HIAA concentrations. Psychiatric symptoms were rated once a week. Olanzapine significantly increased HVA concentrations and the HVA/5-HIAA ratio while 5-HIAA concentrations were not altered. These changes did not significantly correlate with treatment response. A negative correlation was found between HVA concentrations and negative symptoms after olanzapine treatment. In conclusion, olanzapine treatment increases HVA concentrations and the HVA/5-HIAA ratio in CSF of schizophrenic patients, but these changes are unrelated to its clinical efficacy.     

Absence of effect of para-chlorophenylalanine on 5-hydroxyindoleacetic acid in cerebrospinal fluid in man

The effect of para-chlorophenylalanine (PCPA) on the 5-hydroxy-indoleacetic acid (5-HIAA) content in human cerebrospinal fluid (CSF) has been studied. There was no effect on the CSF-content of 5-HIAA 12, 24 or 48 h after a single dose of PCPA 1 g p.o. Neither was there any effect after 1 g/day during 4 days. The increase of 5-HIAA after administration of probenecid was reduced during treatment with PCPA 1 g/day. This reduction, however, is not due to a diminished production of 5-HIAA by PCPA but probably caused by a pharmacological interaction between probenecid and PCPA since the concentrations of probenecid in CSF were lower during administration of PCPA than without that drug.It is concluded that PCPA in the doses used in this study gives no effects on the CSF-concentrations of 5-HIAA.     

Extrapyramidal reactions and amine metabolites in cerebrospinal fluid during haloperidol and clozapine treatment of schizophrenic patients

8 male schizophrenic patients participated in a double-blind, cross over study of the extrapyramidal side-effects of haloperidol and clozapine (acute dystonia, Parkinsonism and tardive dyskinesia), together with their effect on homo-vanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in the cerebrospinal fluid (CSF). Haloperidol (9 mg/day) caused Parkinsonism, reduced tardive dyskinesias and increased the HVA concentration in the CSF. Clozapine (225 mg/day) had no effect on the neurological phenomena but reduced HVA and 5-HIAA concentrations in the CSF. During the discontinuation phase following the administration of haloperidol, tardive dyskinesia occurred or was aggravated; this did not occur after administration of clozapine. Accordingly, it is suggested that clozapine does not induce dopaminergic hypersensibility and, therefore, will not induce tardive dyskinesias.Part of this work was presented at the 9th C.I.N.P. Congress, Paris, July 7–12, 1974.     

Stereoselective metabolism of citalopram in plasma and cerebrospinal fluid of depressive patients: relationship with 5-HIAA in CSF and clinical response

Plasma and cerebrospinal fluid (CSF) concentrations of the enantiomers of citalopram (CIT), its N-demethylated metabolite demethylcitalopram (DCIT) and its deaminated metabolite citalopram propionic acid derivative (CIT-PROP) were measured in plasma and CSF in 22 depressed patients after a 4-week treatment with 40 mg/d citalopram, which was preceded by a 1-week washout period. CSF 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) were measured at baseline and after the 4-week CIT medication period. Patients were assessed clinically, using the Hamilton Depression Rating Scale (21-item HAM-D): at baseline and then at weekly intervals. CSF concentrations of S-CIT and R-CIT were 10.6 +/- 4.3 and 20.9 +/- 6 ng/mL, respectively, and their CSF/plasma ratios were 52% +/- 9% and 48% +/- 6%, respectively. The CIT treatment resulted in a significant decrease (28%) of 5-HIAA (P < 0.0001) and a significant increase (41%) of HVA in the CSF. Multiple linear regression analyses were performed to identify the impact of plasma and CSF CIT enantiomers and its metabolites on CSF monoamine metabolites and clinical response. There were 10 responders as defined by a > or =50% decrease of the HAM-D score (DeltaHAM-D) after the 4-week treatment. DeltaHAM-D correlated (Spearman) significantly with CSF S-CIT (r = - 0.483, P < 0.05), CSF S-CIT-PROP (r = -0.543, P = 0.01) (a metabolite formed from CIT by monoamine oxidase [MAO]) and 5-HIAA decrease (Delta5-HIAA) (r = 0.572, P = 0.01). The demonstrated correlations between pharmacokinetic parameters and the clinical outcome as well as 5-HIAA changes indicate that monitoring of plasma S-CIT, CSF S-CIT and CSF S-CIT-PROP may be of clinical relevance.     

Probenecid-induced accumulation of 5-hydroxyindoleacetic acid and homovanillic acid in rat brain

The accumulation of 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) in rat brain has been examined after probenecid infusion over 8 h. At plasma probenecid concentrations of 200-400 micrograms mL-1 a steady state level in the accumulation of 5-HIAA and HVA was achieved, the increase above the endogenous levels being 135% and 65%, respectively. When the plasma concentration of probenecid rose above 400 micrograms mL-1 there was further accumulation of both 5-HIAA and HVA probably induced by increased neuronal activity or toxicity due to probenecid. The explanation for the plateau of 5-HIAA and HVA obtained over the plasma probenecid concentration interval of 200-400 micrograms mL-1 could be that the levels were reached when there was complete inhibition of active transport, and when the rate of formation of the metabolites equalled the rate of elimination by alternative routes i.e. bulk flow and diffusion. Therefore when probenecid is used to inhibit the active transport of acid monoamine metabolites across the blood-brain barrier, its plasma concentration should be within the range of 200-400 micrograms mL-1.