Hallucinations in patients with major depression. Interactions between CSF monoaminergic and endorphinergic indices

Clomipramine-induced serum prolactin as a marker for serotonin and dopamine turnover: results of an open label study

Central nervous system (CNS) monoamine deficits have been linked to a number of pathological conditions such as major depressive disorder. Individual biological variations in 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) might account for the variation in responses of neurotransmitter systems observed after the administration of clomipramine. The prolactin response to clomipramine has been widely used to assess CNS functioning. This open label study investigates the prolactin response induced by clomipramine in the plasma of healthy volunteers and whether it is related to changes in monoamine metabolites. The effects of clomipramine challenge on prolactin, 5-HIAA, HVA and MHPG were measured in 12 healthy volunteers. Samples were drawn directly before and 50 min after clomipramine infusion. A statistically significant increase in serum prolactin concentrations was measured in women 50 min after CMI infusion, but not in men. We found no significant increases in the serum monoamine metabolite concentrations 50 min after CMI infusion. Changes in HVA and 5-HIAA correlated statistically significantly and positively with the amount of prolactin release in the whole sample. Furthermore, positive correlations were found between ∆(50-0 min) 5-HIAA and ∆(50-0 min) HVA, although we did not find a correlation between ∆(50-0 min) prolactin and ∆(50-0 min) MHPG after clomipramine challenge. The pronounced prolactin release in healthy adult women might indicate a higher physiological sensitivity. Correlations between intra-individual changes in HVA, 5-HIAA and serum prolactin might indicate a central nervous effect of clomipramine on monoamine turnover. We conclude that monoamine changes in relation to prolactin response after clomipramine challenge may be suitable for characterizing the relationship between central serotonergic and dopaminergic function.

Cerebrospinal fluid homovanillic acid is correlated to psychotic features in neurological patients with delirium

OBJECTIVE

The aim of this study was to determine if cerebrospinal fluid (CSF) levels of homovanillic acid (HVA) are related to the clinical features of delirium in a group of patients with acute onset neurological illness.

METHODS

Fifty-one patients with probable acute brain infection were classified as delirious and nondelirious according to Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition (DSM-IV) and Delirium Rating Scale (DRS). CSF HVA concentration was analyzed by high-performance liquid chromatography.

RESULTS

Delirium was present in 60.8% of the total sample. HVA levels were not significantly different between delirious and nondelirious patients. Remarkably, patients with psychotic symptoms shown higher levels of CSF HVA as compared to nonpsychotic patient values. In addition, HVA levels were positively correlated to specific items of DRS such as delusions (r=0.463, P=.001), hallucinations (r=0.438, P=.001), cognitive dysfunction (r=0.286, P=.042) and fluctuation of symptoms (r=0.280, P=.046) in the total sample. Subanalyses excluding patients taking antipsychotic drugs revealed that HVA CSF levels were higher in those patients with delusions, and furthermore, the dopamine metabolite remained positively correlated to delusion subscale of DRS.

CONCLUSIONS

Our results suggest that psychotic symptoms in delirious patients may be related to increased dopamine neurotransmission, as reflected by increased CSF HVA concentration, providing direct evidence to support the dopaminergic theory of psychosis.

Biochemical effects of antidepressant treatment--studies of monoamine metabolites in cerebrospinal fluid and platelet [3H]imipramine binding

Two putative markers of serotonergic function, the concentrations of the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) and the binding parameters of [3H]imipramine to blood platelets, are discussed. Pretreatment concentrations of 5-HIAA in the cerebrospinal fluid (CSF) are lower in depressed patients than in normal controls, and a low concentration of the metabolite is associated with an increased risk of suicide. Many studies have attempted to use pretreatment concentrations of 5-HIAA, of the noradrenaline metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) and of the dopamine metabolite homovanillic acid (HVA) as predictors of therapeutic effect. On the whole, HVA appears to predict the effects of diverse treatments rather better than 5-HIAA. Treatment with antidepressant drugs changes the amine metabolite concentrations in the CSF in a relatively predictable way. Thus, administration of selective inhibitors of serotonin uptake has a more profound effect on CSF 5-HIAA, while noradrenaline uptake inhibitors preferentially reduce CSF MHPG concentrations. The Bmax of [3H]imipramine binding to blood platelets has been found to be lower in untreated depressed patients than in healthy controls in several studies. In a study from our group, three weeks' treatment with the serotonin uptake blockers zimeldine and alaproclate increased Bmax, while neither nortriptyline nor electroconvulsive treatment caused any change in Bmax after this time period. One year after initiation of treatment, patients who had clinically recovered and were no longer taking drugs still had a low Bmax of [3H]imipramine platelet binding. Prophylactic lithium caused a significant, but transient decrease in the Bmax of platelet [3H]imipramine binding in euthymic bipolar patients.

Prolactin secretion in response to haloperidol challenge in delusional (psychotic) and non-delusional depression

Certain studies on measures related to central neurotransmitter activity have demonstrated that in delusional (psychotic) depression there is a dopaminergic dysregulation which distinguishes it from non-psychotic depression. A neuroendocrinologic method to check the degree of DA receptor responsivity is by measuring the prolactin responses to acute intramuscular administration of haloperidol. We studied this possibility by applying the haloperidol test in seven delusional and ten non-delusional depressed patients. All patients met DSM-IV criteria for a major depressive episode, single or recurrent, with or without psychotic features. After a three-week washout period, 5 mg of haloperidol were injected i.m. and blood samples were taken at 0, 30, 60, 90 and 120 minutes. In both trials, significant time effects were observed (elevated prolactin levels, F = 11.36, P = 0.000). However, the prolactin responses to haloperidol did not differ significantly between the two patient groups (F = 0.12, P = 0.97). These data do not show a difference in D(2) receptor responsivity, at least at the hypothalamus-pituitary level, between psychotic and non-psychotic depression.

Somatic treatment of psychotic depression: review and recommendations for practice

The diagnosis, classification, and course of psychotic major depression (PMD) is considered with regard to its status as a distinct syndrome. Several factors, especially biological markers, suggest, although as yet do not confirm, that PMD is distinct from nonpsychotic major depression (NPMD), particularly for the purposes of treatment. This article provides a critical review of somatic treatments for PMD, with attention to problems of inadequate treatment, as well as underused and more recently introduced treatments. The somatic treatment options reviewed include (1) combined antidepressant (AD) and antipsychotic (AP) therapy with tricyclic antidepressants (TCAs) and typical APs; (2) electroconvulsive therapy (ECT); (3) amoxapine; (4) selective serotonin reuptake inhibitors (SSRIs), alone and in combination; (5) several atypical APs, alone and in combination; (6) mood stabilizers and anticonvulsants; and (7) some experimental treatments and surgery. A comprehensive treatment algorithm (heuristic) is presented, which draws on some previous guidelines and the critical review. This heuristic is conservative in its aims, but forward-looking in its recommendations. The status of the TCA plus typical AP regime is challenged as the default first-line treatment, and preferable alternatives are discussed. ECT has been shown to be at least as effective in short-term treatment and should be considered more frequently, especially in severe presentations and as a maintenance treatment. Some single compounds should be considered as first-line monotherapies in less severe cases. For cases in which combined AD+AP regimes are instituted, SSRIs and atypical APs should be used before older classes of drugs are considered. These recommendations aim to minimize the number of treatments used and unwanted effects experienced.

Clinical, magnetic resonance imaging and endocrinological differences between delusional and non-delusional depression in the elderly

OBJECTIVE

To investigate neuroradiological, endocrinological and clinical differences between delusional and non-delusional depression.

DESIGN

A cross-sectional study of depressed subjects.

SETTING

Melbourne, Australia.

PARTICIPANTS

Sixty-one subjects (inpatients) over the age of 55 meeting DSM-III-R criteria for major depression of whom 22 had delusional subtype of depression.

MEASURES

Clinical assessment, including documentation of vascular risk factors. Cognitive assessment by the Cambridge Cognitive Examination (CAMCOG). Magnetic resonance imaging (MRI) scans were performed on a 0.3 Tesla scanner with temporal lobe atrophy, periventricular lesions (PVL) and deep white matter lesions (DWML) rated visually on 4-point scales. A standard 1 mg dexamethasone suppression test (DST) was performed.

RESULTS

Subjects with delusional depression had significantly more vascular risk factors than those without delusions. There were no differences in measures of temporal lobe atrophy, PVL, DST results or cognitive test scores, though there was a non-significant trend for DWML to be more prevalent in those with delusions. Delusional depression was associated with a shorter duration of history and more frequent treatment with ECT.

CONCLUSIONS

The increase in vascular risk factors and trend towards greater DWML on MRI suggests an organic contribution to delusional depression in the elderly. In contrast to some previous reports, we found no differences in cortical MRI appearance or neuroendocrine measures between groups.

Association of biogenic amine metabolites with symptomatology in delusional (psychotic) and nondelusional depressed patients

1. The levels of the main norepinephrine, serotonin, and dopamine metabolite excretion in the urine, MHPG, 5HIAA and HVA respectively, were measured in 84 patients with major depressive disorder, 34 delusional (psychotic) and 50 nondelusional (DSM-III-R criteria). 2. Associations with the 17 items of the HDRS were evaluated using the multiple regression analysis model. In the delusional group, MHPG excretion was positively related to the scores in the items of depressed mood (p = 0.04), middle insomnia (p = 0.008) and genital symptoms (p = 0.001). 5HIAA excretion was negatively associated with late insomnia (p = 0.02), work and interests (p = 0.001) and genital symptoms (p = 0.007). HVA was positively related to agitation (p = 0.043). In the nondelusional group the only association found was between agitation and HVA excretion (p = 0.03).

Biogenic amine metabolites in delusional (psychotic) depression and melancholia subtypes of major depression

1. The levels of the urinary main metabolites of norepinephrine 3-methoxy-4-hydroxyphenylglycol (MHPG), of dopamine homovanillic acid (HVA) and of serotonin 5-hydroxyindoleacetic acid (5-HIAA) were measured in 84 patients with major depressive disorder, 34 delusional and 50 nondelusional. Melancholia subtype was also defined (N = 62). 2. MHPG was significantly higher in the delusional depressed group (p = 0.023). Female patients with delusional major depression also had significantly higher HVA excretion than female patients with non delusional major depression (p = 0.036). 5-HIAA excretion was similar in the two patient subgroups. 3. No significant differences in the three monoamine metabolites were found between the melancholic and nonmelancholic depressed patients.

Clinical investigation of monoamine neurotransmitter interactions

Monoamine neurotransmitter systems are widely thought to be involved in the pathophysiology of affective disorders and schizophrenia and the mechanism of action of antidepressant and antipsychotic drugs. Previous clinical studies have focused on individual monoamine function in isolation, even though a large number of preclinical studies have demonstrated that monoamine neurotransmitter systems interact with one another. In the present paper, preclinical data on monoamine neurotransmitter interactions are reviewed, and two methods for examining monoamine neurotransmitter system interactions in clinical data are presented. One of the best replicated findings in biological psychiatry is that monoamine metabolites in CSF correlate with one another. The degree of correlation may be in part a measure of the degree of interaction between the parent monoamine neurotransmitter systems. Another approach to studying interactions is the use of HVA/5HIAA and HVA/MHPG ratios as an index of interactions between 5HT-DA and NE-DA. When these methods are applied in schizophrenia, patients are found to have decreased monoamine metabolite correlations compared to normal controls. Metabolite correlations increase significantly after antipsychotic treatment, and the HVA/5HIAA and HVA/MPHG ratios also increase, suggesting that neuroleptics may act in part by strengthening interactions between monoamines. BPRS ratings are negatively correlated with HVA/5HIAA and HVA/MHPG so that patients with higher ratios have fewer symptoms, particularly after treatment. These results provide direct experimental support for hypotheses suggesting that interactions between monoamine neurotransmitters are important in schizophrenia. Some of the effects of the atypical neuroleptic, clozapine, on metabolite correlations and ratios are also discussed.

Role of the dopaminergic system in depression

A hypothesis implicating dopamine in depression was proposed over 15 years ago (Randrup et al 1975). The identification of multiple new subtypes of dopamine receptors and evolving views regarding the function of the dopamine systems in the brain require a reexamination of this hypothesis. Results from studies in depression, Parkinson's disease, and animal models of depression suggest a deficiency of dopamine in depression. Dopamine precursors, dopamine agonists, and dopamine reuptake inhibitors show therapeutic efficacy in depression. Electroconvulsive therapy (ECT) and standard pharmacological antidepressants enhance dopamine function. Studies using receptor-specific drugs in clinical trials and neuroimaging studies are needed to further clarify the role of dopamine in depression.

Relationships between clinical symptoms and monoamine metabolite concentrations in biochemically defined subgroups of depressed patients

In 28 patients with primary depression, relationships were sought between rating scores on the Montgomery-Asberg Depression Rating Scale and the concentrations of the monoamine metabolites 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and 4-hydroxy-3-methoxyphenylglycol (HMPG) in cerebrospinal fluid (CSF). Among the single items in the rating scale, reported sadness correlated negatively with HMPG. No other significant relationships were found in the total group of patients. However, in subgroups with low or high concentrations of monoamine metabolites, several significant relationships were found, such as a negative correlation between inner tension and concentration difficulties, respectively, and 5-HIAA in the low-HMPG subgroup. Curvilinear relationships were found between pessimistic thoughts and 5-HIAA in the high-5-HIAA subgroup and between apparent sadness and 5-HIAA in the low-HMPG subgroup. Suicidal thoughts tended to correlate in a curvilinear way with the ratio of HMPG/5-HIAA in the low-HVA and the high-HMPG subgroups, but the curves were mirrored. The results indicate that relationships between clinical symptoms and monoamine metabolite homeostasis in CSF are qualitatively and quantitatively different in defined high-and low-monoamine subgroups of depressed patients.

CSF amine metabolites and depression

Cerebrospinal fluid (CSF) amine metabolites were measured in 37 male subjects with major depressive disorder. Scores on the Hamilton Rating Scale for Depression (HRSD) correlated significantly with 5-hydroxyindoleacetic acid (5HIAA) and with homovanillic acid (HVA). In addition, the single suicide item of the HRSD correlated significantly with 5HIAA. Further, 5HIAA and HVA correlated significantly with each other. There was a significant positive correlation between HVA and two HRSD items, the depersonalization/derealization item and the paranoid item. Since lumbar CSF metabolite concentrations may reflect central nervous system activity of parent amines, these data suggest a relationship between depression and decreased dopaminergic and serotonergic activity.

Psychotic and nonpsychotic depressions: II. Platelet MAO activity, plasma catecholamines, cortisol, and specific symptoms

Preliminary data are presented on levels of plasma cortisol, dopamine (DA), epinephrine (EPI), and norepinephrine (NE) before and after dexamethasone in 22 depressed patients (of whom 4 were psychotic). Platelet monoamine oxidase (MAO) activity, determined in 19 of the depressed patients, was significantly higher in the 4 psychotic patients than it was in the 15 nonpsychotic patients. Positive correlations were observed before and after dexamethasone among cortisol, DA, EPI, and platelet MAO. After dexamethasone, plasma NE correlated negatively with DA, EPI, and cortisol. The various correlations were due largely to the inclusion of the psychotic depressive subgroup. Data are also presented on the relationships between these biological measures and specific signs and symptoms.

CSF levels of receptor-active endorphins in schizophrenic patients: correlations with symptomatology and monoamine metabolites

Cerebrospinal fluid (CSF) levels of an opioid receptor-active, chromatographically separated endorphin fraction (Fraction I) were measured in 45 schizophrenic patients and 18 healthy volunteers. Significantly increased levels of Fraction I differentiated the patient group from controls, with no difference being found between newly admitted untreated and chronic previously neuroleptic-treated subjects. Fraction I levels did not correlate with age, weight, height, duration of illness, total time hospitalized, or age when symptoms first appeared. No differences were found between patients with or without a family history of schizophrenia. Fraction I levels were negatively correlated with "hallucinations" and "indecision" on the Comprehensive Psychopathological Rating Scale. Increased levels of Fraction I were associated with low levels of the dopamine metabolite homovanillic acid in drug-free schizophrenics. This relationship was not present after neuroleptic treatment or in healthy controls. No relationship was found between Fraction I and the serotonin metabolite 5-hydroxyindoleacetic acid. Neuroleptic treatment did not significantly change Fraction I levels; when only patients above the control range were considered, however, a significant decrease was observed. The data support our previous hypothesis of an increased opioid activity in schizophrenia and further indicate a concomitant dysfunction of brain endorphin and dopamine activity in schizophrenic patients.

Endogenous opiates: 1985

This paper is the eighth installment of our annual review of research involving the endogenous opiate peptides. It is restricted to the non-analgesic and behavioral studies of the opiate peptides published in 1985. The specific topics this year include stress, tolerance and dependence, eating, drinking and alcohol consumption, gastrointestinal and renal activity, mental illness, learning and memory, cardiovascular responses, respiration and thermoregulation, seizures and neurological disorders, activity, and some other selected topics.