Monoamine metabolites in the CSF of epileptic patients.

To assess the possible role of amine neurotransmitters in human epilepsy, we measured metabolites of serotonin (5-hydroxyindoleacetic acid [5-HIAA]), dopamine (homovanillic acid [HVA]), and norepinephrine (3-methoxy-4-hydroxyphenylethylene glycol [MHPG]) in the lumbar cerebrospinal fluid (CSF) of patients with partial complex seizures and in neurologic controls. Untreated epileptic patients had lower concentrations of 5-HIAA and HVA in the lumbar CSF than the controls, but the differences were not statistically significant. Among epileptic patients receiving effective antiepileptic drug treatment, the HVA concentration was within the control range. Mean MHPG concentrations were similar in patients and controls. From the epileptic patients whose CSF was obtained at pneumoencephalography we obtained a second sample of CSF that was originally in the basal cisterns. No significant differences between treated and untreated patients were found for any of the three metabolites. The concentrations of HVA and 5-HIAA were higher in cisternal than in lumbar CSF, but there was no such gradient for MHPG.     

CONCENTRATIONS OF MONOAMINE METABOLITES IN HUMAN LUMBAR AND CISTERNAL CEREBROSPINAL FLUID

5HIAA and HVA were determined in successive samples of CSF withdrawn at the lumbar and cisternal levels in connection with gas myelographic examinations in 16 patients. The mean of 5-HIAA in the first cisternal samples were 83 ng/ml (n equal to 8) and of HVA 143 NG/ML (N equal to 7). A sharp increase in the concentration of both metabolites, but particulary of HVA, was seen in successive lumbar samples. The ratio of cisternal/lumbar 5-HIAA was 3/1, and of HVA 10/1 in one patient in whom lumbar and cisternal CSF were obtained with 2 weeks' interval. The concentrations of monoamine metabolites in CSF obtained at lumbar puncture are thus highly dependent on the amount of fluid withdrawn. This fact should be taken into consideration when different materials are compared.     

Monoamine metabolites in cerebrospinal fluid in multiple sclerosis.

The concentrations of homovanillic acid (HVA), 5-hydroxyindolylacetic acid (5-HIAA), and 4-hydroxy, 3-methoxyphenylethylene glycol (MHPG) were estimated in the lumbar cerebrospinal fluid (CSF) of control subjects and in some patients who probably, and others who definitely, suffered from multiple sclerosis (MS). In the control group, the concentration of HVA was lower in people who underwent lumbar puncture having fasted and been recumbent for 12 hours before the procedure than in those from whom CSF was obtained under non-standardised conditions. These studies demonstrate that a standardised procedure for lumbar puncture is required in order to obtain meaningful results. In patients suffering from MS the CSF 5-HIAA concentrations were significantly lower than in comparable controls but the HVA concentrations did not differ. There was no relationship between metabolite concentrations, site of lesion, the duration of the disease, gamma-globulin levels nor the occurrence of relapse within the previous month.     

Cerebrospinal fluid 5-hydroxyindoleacetic acid as an index of central serotonergic processes

Faulty transmission in the central serotonin and catecholamine systems may be involved in some psychiatric and neurological conditions. Central monoamine metabolism can be studied by measuring amine metabolites in the lumbar cerebrospinal fluid (CSF), but results to date have been inconsistent. Since most studies have analyzed lumbar CSF, one reason for the inconsistencies may be that lumbar fluid does not reflect brain amine metabolism. We measured 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid (HVA) in serial CSF samples obtained in connection with pneumoencephalographic (PEG) examinations: through seven samples of equal volume, a gradual increase was found for both metabolites in 14 neurological patients, and the first and last fractions were statistically significantly correlated. In addition, a small series of cisternal CSF samples from psychiatric (depressed and alcoholic) and neurological patients were analyzed for 5HIAA. Frequency distribution in cisternal CSF was similar to that of lumbar values, although the levels were about twice as high, close to those found in the last PEG fractions. There were no significant differences between patient groups either in cisternal or lumbar CSF 5HIAA. These findings suggest that while there is an ascending gradient, lumbar CSF samples do reflect amine metabolite concentrations of the more central fluid. No disease-specific differences in cisternal CSF were found which were absent in the lumbar fluid.     

Self-rated childhood emotional neglect and CSF monoamine indices in abstinent cocaine-abusing adults: possible implications for suicidal behavior

Non-human primate studies suggest that early environmental influences may have an enduring effect on central serotonin function. Therefore, it was decided to examine in humans whether childhood trauma might be related to cerebrospinal fluid (CSF) concentrations of the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) as an adult. A total of 29 withdrawn cocaine-dependent patients completed the Childhood Trauma Questionnaire. They also had a lumbar puncture for determination of CSF concentrations of 5-HIAA. CSF concentrations of the dopamine metabolite homovanillic acid (HVA) were also determined. Childhood emotional neglect scores showed significant negative correlations with CSF levels of 5-HIAA and HVA, and patients with emotional neglect scores above the median had significantly lower CSF 5-HIAA and HVA levels than patients with emotional neglect scores at or below the median. These findings suggest the possibility that childhood trauma may have an effect on central monoamine function as an adult.     

Sites of origin in the central nervous system of monoamine metabolites measured in human cerebrospinal fluid

The concentrations of homovanillic acid (HVA) and 5-hydroxyindole-acetic acid (5-HIAA) were measured in five cases with partial or complete block of CSF circulation, at various levels. Determinations were made in both a lumbar and a cisternal, or `mixed', sample obtained during pneumoencephalography. Most of the HVA appears to enter the ventricular system at the lateral ventricles, whereas much of the 5-HIAA in CSF originates in lower neuronal structures, including the spinal cord. The spinal contribution to the 5-HIAA content of lumbar CSF is of the order of 23-37%.     

Homovanillic acid and 5-hydroxyindoleacetic acid in lumbar cerebrospinal fluid in children with afebrile and febrile convulsions

The concentrations of 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) were measured in lumbar cerebrospinal fluid (CSF) from five groups of children: (1) afebrile controls (2) febrile controls, (3) children with afebrile convulsions, which included children with established idiopathic epilepsy, (4) children with first febrile convulsions, and (5) children with repeated febrile convulsions. There were no significant differences between the metabolite levels in the five diagnostic groups. The CSF concentrations of 5-HIAA and HVA in these children, with a mean age of 2.5 years, were about twice the levels found in adults.     

CSF monoamine metabolites in dementia of the Alzheimer type and controls: Evidence for lower levels of homovanillic acid and 5-hydroxyindoleacetic acid in patients

The monoamine metabolites 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) in lumbar cerebrospinal fluid (CSF) were measured in 15 patients with dementia of the Alzheimer type (DAT) and 48 controls by means of a sensitive liquid chromotagraphic method. Relative to a large group of control subjects, the mean CSF 5-HIAA and HVA levels in patients with DAT appeared to be significantly lower. This finding appeared to be sex-related, in that the decrease in CSF monoamine metabolite levels could be attributed predominantly to male patients. A statistically significant relationship was found between 5-HIAA and HVA in both patients and controls. Linear regression analysis revealed a statistically significant positive relationship between age and CSF HVA in female controls only. No relationship was found between 5-HIAA and age either in patients or in controls. It is concluded that CSF 5-HIAA and HVA levels are decreased in male patients with DAT, probably signalling a sex-related change in serotonin and probably dopamine functioning in the central nervous system.     

Reduced brain delivery of homovanillic acid to cerebrospinal fluid during human aging

BACKGROUND: Markers of human brain dopamine metabolism are reported to decline with age. However, the cerebrospinal fluid (CSF) concentration of homovanillic acid (HVA), a major dopamine metabolite, is reported to not change or to increase in elderly individuals. OBJECTIVE: To estimate the rate of delivery of HVA from the brain to CSF, taking into account the HVA concentration gradient in the spinal subarachnoid space and CSF flow. METHODS: Homovanillic acid concentrations were measured in 5 serial 6-mL aliquots of CSF removed from the L3-4 or L4-5 interspaces of 7 healthy young (mean +/- SD age, 28.7 +/- 4.6 years) subjects and 7 healthy elderly (mean +/- SD age, 77.1 +/- 6.3 years) subjects. Cisterna magna HVA concentrations were estimated from the slopes of the HVA concentrations along the spinal subarachnoid space. The products of cisternal HVA concentrations and published values for CSF flow were used to estimate lower limits for brain delivery of HVA to CSF, according to the Fick principle. RESULTS: The mean +/- SD HVA concentration in the initial lumbar CSF sample in the young subjects, 116 +/- 66 pmol/mL, did not differ significantly from 140 +/- 86 pmol/mL in the elderly subjects. Estimated cisternal HVA concentrations equaled 704 and 640 pmol/mL, respectively, in the young and elderly subjects. Multiplying these concentrations by CSF flow rates of 591 and 294 mL/d, respectively, gave lower limits for rates of delivery of HVA from the brain to CSF. These rates equaled 416 and 175 nmol/d, respectively. CONCLUSION: A 50% decline in the lower limit for the rate of HVA delivery from the brain to CSF in elderly individuals is consistent with other evidence that brain dopaminergic neurotransmission declines with age.     

Low lumbar CSF levels of homovanillic acid and 5-hydroxyindoleacetic acid in multiple system atrophy with autonomic failure.

Low lumbar CSF concentrations of homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in patients with multiple system atrophy attended by autonomic failure (MSA) reflect decreased activity in central dopaminergic and serotonergic pathways. These neurochemical changes are consistent with the neuropathological involvement in MSA and distinguish such patients from those with pure autonomic failure who have normal CSF metabolite levels.     

CSF monoamine metabolites of depressed patients during illness and after recovery

Repeated lumbar punctures in 16 healthy volunteers showed reproducible concentrations of 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) in cerebrospinal fluid (CSF). In seven depressed patients, studied during two or three illness periods, the metabolite concentrations were also fairly stable. In 11 patients CSF concentrations of 5-HIAA, but not of HVA, were higher after recovery than during depression. This increase of 5-HIAA after recovery was confined to patients whose initial serotonin metabolite levels were low. The finding constitutes further evidence of a biochemical heterogeneity within the depressive disorders, and suggests that patients whose CSF 5-HIAA is low during a depressive episode may have a less stable serotonin system than other patients with depressive illness.     

Influence of gonadal steroids on human and monkey cerebrospinal fluid homovanillic acid concentrations

The influence of gonadal steroids on central dopaminergic function was assessed by measuring concentrations of the dopamine metabolite homovanillic acid (HVA) in cerebrospinal fluid (CSF) in humans and monkeys. CSF HVA and 5-hydroxyindoleacetic acid (5-HIAA) concentrations were measured by high performance liquid chromatography with electrochemical detection. Thirteen intact adult female monkeys (Macaca fascicularis) and six ovariectomized monkeys had a lumbar puncture to collect CSF. Ovariectomized monkeys had higher HVA concentrations in their CSF while 5-HIAA levels remained unchanged. In a second experiment, 40 human subjects were divided into six groups as follows: I, women with menses; II, menopaused or ovariectomized women taking estrogens; III, hysterectomized women of unknown hormonal status; IV, menopaused or ovariectomized women; V, women taking dopaminergic drugs or showing signs of parkinsonism; VI, men. CSF was collected by lumbar puncture. 5-HIAA levels were constant. Hysterectomized (III) as well as menopaused or ovariectomized (IV) women had significantly (p less than 0.05) higher CSF HVA concentrations compared to men. While women in group IV were older, those in group III were of the same age as the men. These results provide further evidence for the role of endogenous ovarian factors as modulators of central dopaminergic activity.     

CSF studies on the relationship between dopamine and 5-hydroxytryptamine in Parkinsonism and other movement disorders.

In Parkinson's disease, the concentration of homovanillic acid (HVA) was reduced in lumbar CSF from patients with idiopathic Parkinsonism (n = 54, P less than 0.05) and post-encephalitic Parkinsonism (n = 19, P less than 0.01). The reduction in the concentrations of 5-hydroxyindolylacetic acid (5-HIAA) was not significant, and there was no alteration in the levels of 4-hydroxy-3-methoxyphenylethylene glycol (MHPG). Treatment with L-dopa increased the concentration of HVA in the CSF (P less than 0.05) but had no effect on the levels of 5-HIAA and MHPG. Carbidopa given in combinations with L-dopa produced similar CSF concentrations of dopa as did L-dopa alone but caused less than half the rise in HVA. Fourteen patients who became functionally independent on treatment with L-dopa had higher 5-HIAA levels than 23 patients who showed no such improvement (P less than 0.001), suggesting that intact 5-hydroxyltryptamine neurones may be important in the therapeutic response to L-dopa. In a variety of movement disorders, the levels of HVA, 5-HIAA, and MHPG were not significantly different from age-matched controls. Treatment with tetrabenazine did not significantly alter the metabolite levels in patients in whom it produced either improvement, or side effects.     

Monoamine acid metabolites and cerebrospinal fluid dynamics in normal pressure hydrocephalus: preliminary results.

Lumbar and ventricular CSF concentration of homovanillic acid (HVA) and 5-hydroxy-indole-acetic acid (5-HIAA) have been determined in 13 patients admitted to hospital for suspected normal pressure hydrocephalus. Low values of HVA in lumbar CSF were found in all patients with reduced CSF absorption and CSF flow inversion. The HVA lumbar concentration remained low after shunt procedure; it increased if obstruction of the shunt occurred. The ventricular CSF concentration of HVA was normal before surgery; it became higher, in two cases, after surgery. No important variations were found in the lumbar and ventricular CSF concentration of 5-HIAA. The possible mechanisms and diagnostic value of these findings are discussed.     

Tryptophan and biogenic amine metabolites in post-mortem human cisternal fluid: effects of post-mortem interval and agonal time.

Cisternal fluid (CF) tryptophan (TRP), 5-hydroxyindole-3-acetic acid (5-HIAA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) concentrations were measured from 40 adult cadavers. They were divided into 4 groups (n = 10 in each group), with samples taken 2, 4, 10 and 24 h after death. The CF concentrations of TRP and all determined biogenic amine metabolites were distinctly higher than in lumbar CSF during life, and concentrations of 5-HIAA were also higher in post-mortem samples than in cisternal or ventricular CSF in living humans. The means of the samples of 5-HIAA, DOPAC, HVA and MHPG were not statistically significantly different over time, but some trends were evident. TRP concentrations in CF increased linearly with time (from 4.6 to 23.6 mumol/l, P less than 0.001). CF DOPAC and HVA concentrations were dependent on agonal time and dopamine infusions. Our results imply that both ante-mortem and post-mortem conditions may influence monoamine metabolite and TRP concentrations in CF. These conditions should be accounted for in studies using post-mortem samples to study differences between patient groups in CNS neurochemistry.     

Aberrant monoamine metabolite levels in CSF and family history of schizophrenia. Their relationships in schizophrenic patients

In 36 drug-free schizophrenic patients, lumbar CSF was analyzed by mass fragmentography for the major monoaminergic transmitter metabolites 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG). High or deviant concentrations of 5-HIAA were significantly related to a family history of schizophrenia. For patients with deviant 5-HIAA levels, the probability for a family history of schizophrenia was eight times higher than in subjects with normal values. High concentrations of HVA also tended to be significantly related to a family history of schizoprenia. The majority of schizophrenic patients, who lacked family history for the disorder, had normal monoamine metabolite concentrations in CSF. The results suggest a coupling between biochemical variables related to central serotonin and dopamine metabolism and forms of schizophrenia that have a familial disposition.     

d-amino acid oxidase activator gene (DAOA) variation affects cerebrospinal fluid homovanillic acid concentrations in healthy Caucasians

The D-amino acid oxidase activator (DAOA) protein regulates the function of D-amino oxidase (DAO), an enzyme that catalyzes the oxidative deamination of D-3,4-dihydroxyphenylalanine (D-DOPA) and D-serine. D-DOPA is converted to L-3,4-DOPA, a precursor of dopamine, whereas D-serine participates in glutamatergic transmission. We hypothesized that DAOA polymorphisms are associated with dopamine, serotonin and noradrenaline turnover in the human brain. Four single-nucleotide polymorphisms, previously reported to be associated with schizophrenia, were genotyped. Cerebrospinal fluid (CSF) samples were drawn by lumbar puncture, and the 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) were measured. Two of the investigated polymorphisms, rs3918342 and rs1421292, were significantly associated with CSF HVA concentrations. Rs3918342 was found to be nominally associated with CSF 5-HIAA concentrations. None of the polymorphisms were significantly associated with MHPG concentrations. Our results indicate that DAOA gene variation affects dopamine turnover in healthy individuals, suggesting that disturbed dopamine turnover is a possible mechanism behind the observed associations between genetic variation in DAOA and behavioral phenotypes in humans.     

CSF-amine metabolites in depression, dementia and in controls

Lumbar CSF concentration of 5-HIAA, MHPG, and HVA were measured in patients with depression, dementia due to normal pressure hydrocephalus (NPH) and in controls. Moreover, ventricular concentrations of the metabolites were measured in patients with NPH. It was aimed to match patients and controls for age, sex, and body height. Non-parametric statistics were used throughout the study. No differences in lumbar concentrations of CSF 5-HIAA, MHPG and HVA were found between the different diagnostic groups. A ventriculo-lumbar gradient of 5-HIAA and HVA being 4:1 and 5:1, respectively, was found in patients with NPH. No correlation between the difference in ventricular and lumbar concentrations and body height was found, suggesting that body height may be an inaccurate measure for the rostro-caudal gradient. Moreover, no correlation between ventricular and lumbar levels of 5-HIAA and HVA was seen.     

Use of cerebrospinal fluid drawn at pneumoencephalography in the study of monoamine metabolism in man

Concentrations of homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were significantly higher in CSF obtained after injection of air during pneumoencephalography (PEG) than in lumbar CSF, as drawn before the injection. There was a high correlation between levels in the `mixed' and lumbar samples of CSF in the case of each of the two acids. The concentration of lumbar HVA, but not that of 5-HIAA, was negatively correlated with CSF pressure. 5-HIAA levels were low in both samples of CSF in a group of epileptics, by comparison with controls. In two patients with Kufs disease and in one with Niemann-Pick disease, the concentration of HVA was very low in the lumbar sample. The application of a standardized PEG technique in the study of monoamine metabolism in man is suggested.     

Spinal reflexes and the concentrations of 5-HIAA, MHPG, and HVA in lumbar cereborspinal fluid after spinal lesions in man.

Descending bulbospinal pathways that employ specific neurotransmitter substances are known to be capable of modulating segmental reflex activity in the experimental animal. To determine whether this might also occur in man correlations have been sought between the activity in spinal reflex pathways and the lumbar cerebrospinal fluid (CSF) concentrations of 5-hydroxyindolacetic acid (5-HIAA), 3 methoxy-4-hydroxyphenylglycol (MHPG), and homovanillic acid (HVA) in 12 patients with complete or virtually complete spinal lesions. The concentrations of 5-HIAA and MHPG in lumbar CSF ARE REDUCED AFTER COMPLETE OR VIRTUALLY COMPLETE SPINAL LESIONS IN MAN. This may occur within 18 days of the lesion. MHPG concentrations appear to be inversely related to the level of the lesion. The HVA concentration in lumbar CSF is reduced when there is obstruction of the CSF pathways. No relationship could be demonstrated between the concentrations of 5-HIAA or MHPG in lumbar CSF and the activity in the spinal monosynaptic pathway (estimated from the proportion of the motoneurone pool activated by the Achilles tendon reflex or H reflex) or the activity of a spinal inhibitory mechanism (estimated by the degree of vibratory inhibition of the monosynaptic reflex). Patients with a tonic vibration reflex (TVR) tended to have higher MHPG levels. There appeared to be an association between low CSF HVA and enhanced vibratory inhibition of the monosynaptic reflex in the nine patients whose spinal lesions were complete.