Urinary MHPG, platelet 3H-imipramine binding and symptomatology in depression: an exploratory study of clinical heterogeneity

Association between the scores on the general health questionnaire-28 and the saliva levels of 3-methoxy-4-hydroxyphenylglycol in normal volunteers

To access the saliva level of 3-methoxy-4-hydroxy-phenylglycol (sMHPG) as an index of mental health in normal volunteers, we investigated the relationship between the sMHPG and the scores on the general health questionnaire-28 (GHQ-28). A total of 270 normal volunteers answered the GHQ-28 and the sMHPG levels were determined. The sMHPG levels in women and men were comparable. There was a significant negative correlation between the social dysfunction score on the GHQ-28 and sMHPG levels in women (P=0.0035), but not in men. Moreover, the sMHPG levels also correlated with the total GHQ-28 score (P=0.0205), the anxiety and the insomnia score (P=0.0306) in women. These data indicate a high social dysfunction score on the GHQ-28 to be associated with a reduced noradrenergic neuronal tone thus possibly reflecting psychomotor retardation in women.

Associations between baseline plasma MHPG (3-methoxy-4-hydroxyphenylglycol) levels and clinical responses with respect to milnacipran versus paroxetine treatment

The purpose of this study was to investigate the effects of milnacipran and paroxetine on plasma levels of catecholamine metabolites, and we attempted to elucidate the differences between the mechanisms of these drugs in catecholaminergic neurons. In depressed patients, we investigated the relationships among pretreatment levels of catecholamine metabolites, the changes in plasma catecholamine metabolite levels before and after administration of milnacipran or paroxetine, and clinical response to these drugs. Responders to milnacipran showed lower pretreatment levels of plasma 3-methoxy-4-hydroxyphenylglycol (pMHPG) than did nonresponders to milnacipran; there was also a positive correlation between changes in pMHPG levels and percent improvement of the score on the 17-item Hamilton Rating Scale for Depression (HRSD). On the other hand, responders to paroxetine showed higher pretreatment levels of pMHPG than did nonresponders to paroxetine, and a negative correlation was observed between changes in pMHPG levels and percent improvement of the HRSD score. However, a significant difference was not observed in the pretreatment plasma level of homovanillic acid between responders and nonresponders to treatment with milnacipran or paroxetine. These results suggest that there is an association between baseline pMHPG levels and clinical responses with respect to milnacipran versus paroxetine treatment.

Unipolar-bipolar dichotomy of mood disorders is supported by noradrenergic brainstem system morphology

BACKGROUND

The biological basis of unipolar-bipolar dichotomy of mood disorders was investigated in this postmortem study by morphological comparison of the locus coeruleus (LC) as the main source of noradrenergic transmission in the brain.

METHODS

Numbers and the rostro-caudal as well as ventro-dorsal distribution of neuromelanin-containing neurones in the LC were determined in brainstem of 12 patients with bipolar disorder (n = 6) or major depression (n = 6), and 12 normal comparison subjects.

RESULTS

Bipolar patients had significantly more neurones on both sides of the LC as a whole than patients with major depression. Topographical analysis revealed that this difference was restricted to the rostral two thirds and the dorsal part of the LC, in which bipolar patients showed at least a trend to higher neurone numbers as compared to unipolar patients or to controls.

LIMITATIONS

Small case numbers.

CONCLUSIONS

Results suggest differences of innervation arising from the LC of bipolar patients as compared to patients with major depression. These first data of brainstem transmitter system morphology in unipolar and bipolar disorder are in line with neuroanatomical studies of other brain regions indicating a biological basis of the unipolar-bipolar dichotomy of mood disorders.

Psychomotor performance and monoamine function in bipolar and unipolar affective disorders

BACKGROUND

Affective disorders are associated with prominent psychomotor abnormalities that may be related to changes in arousal or motivation due to altered catecholamine function.

METHODS

We investigated relationships between performance on psychomotor tests of motor speed (reaction time and tapping speed) and visual tracking (trail making and dot placement) and catecholamine system function including cerebrospinal fluid (CSF) or urinary concentrations of catecholamines or their metabolites. Subjects were medicine-free inpatients with unipolar depression or with manic, depressive, or mixed episodes of bipolar disorder, and healthy controls matched by gender and stratified by age.

RESULTS

Unipolar and bipolar depressed patients were impaired in motor speed, dexterity, and visual tracking, whereas manic and mixed patients did not differ from controls. Tapping speed correlated positively with CSF 3-methoxy-4-hydroxyphenylglycol in healthy controls and with CSF homovanillic acid in bipolar depressed subjects. Increased catecholamine function correlated with slowing in all other measures for patients with bipolar disorder. Relationships between catecholamines and psychomotor function were weaker in unipolar depressed subjects. Psychomotor function was related to severity of depression in bipolar, but not in unipolar, patients.

CONCLUSIONS

These data suggest that catecholamine systems are associated with increased arousal and psychomotor impairment in patients with bipolar disorder. Similar behavioral changes have different neurotransmitter relationships in unipolar disorder.

Urinary levels of 3-methoxy-4-hydroxyphenylglycol predict symptom severity in selected patients with unipolar depression

There are preliminary biological data that support the validity of subtyping depressed patients by family history into depressive spectrum disease (DSD) and non-DSD groups. We hypothesized that a relatively homogeneous group of depressed patients might show an association between symptom severity and the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG). Twenty-four patients with non-DSD depression showed a relationship between urinary levels of MHPG and the severity of several depressive symptoms. There were no associations between MHPG and symptom severity for 38 DSD patients. This study provides additional support for the validity of family history approaches to subtyping depression. The data also suggest that norepinephrine may be involved in some way in the pathogenesis of symptoms in non-DSD depression.

Urinary MHPG and clinical symptoms in patients with unipolar depression

The relationship between levels of urinary 3-methoxy-4-hydroxyphenylglycol (MHPG) and symptom scores on the Hamilton Rating Scale for Depression was examined in 31 patients with unipolar depression. Patients with either low MHPG or high MHPG showed significant sleep disturbance in the form of early morning awakening. Patients with mid-range or high MHPG showed decreased work and activities. Endogenomorphy factor scores represented a blend of these findings.

Sleep disorders and anxiety as symptom profiles of sympathoadrenal system hyperactivity in major depression

Recently, it has been reported that major depression is accompanied by an increased sympathoadrenal system (SAS) activity. In order to study the psychopathological correlates of SAS activity in depression, the authors measured the 24 h urinary excretion of catecholamines (CA), i.e., noradrenaline (NE), adrenaline (E), dopamine (DA) and the NE/E metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in 80 unipolar depressed subjects. The excretion of these indices of SAS activity have been studied in relation to the depressive items of the Structured Clinical Interview for DSM-III (SCID) and the Hamilton Depression Rating Scale (HDRS). There were significant positive correlations between the SCID item sleep disorders and the HDRS item middle insomnia, on the one hand, and NE, E and DA excretion, on the other. The MHPG excretion in 24 h urine was significantly and negatively related to somatic anxiety and hypochondriasis. It is suggested that these intertwined relationships between increased CA turnover, sleep discontinuity and anxiety may reflect the occurrence of a hyperarousal state in some major depressives that may be regarded as a coping response to various putative noxious stimuli.

Noradrenergic and serotoninergic depression?

The aim of this study was to test the hypothesis of noradrenergic and serotoninergic depressive subtypes. For this purpose, the correlation between three variables was investigated: urinary 3-methoxy-4-hydroxyphenylglycol (MHPG), dexamethasone suppression test (DST), and clinical response profiles to clomipramine and maprotiline, the effects of which are relatively selective on the uptake of noradrenaline (NA) and 5-hydroxytryptamine (5HT). Our results showed no correlation between these measures. Therefore, the hypothesis of two subtypes of depression was not supported. The only significant finding in this study was the obvious decrease in MHPG excretion during the antidepressant treatment in the group with high pretreatment MHPG.

Decreased seasonal mesor of platelet 3H-imipramine binding in depression

Seasonal cycles of platelet 3H-imipramine binding were compared in 49 endogenous unipolar depressed patients and 20 normal volunteers. A significant sinusoidal component was detected in the Bmax of binding in both patients and controls with similar amplitudes and seasonal peaks. However, the yearly average (mesor) of the patient group was significantly lower (20.0%) than that of the normal controls. The results support earlier claims of a diminished platelet binding in endogenous depression and indicate that this decrease was still evident in the presence of a 48.2% (controls) to 65.8% (patients) seasonal variation. Control Bmax values were normally distributed about a best-fit mean (cosinor fit). In contrast, patient values appeared to be bimodally distributed with one mode that was similar to controls and one mode that was substantially lower. In general, psychiatric symptoms failed to distinguish between patients with high and low platelet binding and no correlation was found between Bmax and severity of illness (HAM-D).

Seasonal changes in cyanoimipramine specific platelet 3H-imipramine binding in depression

Seasonal variations in cyanoimipramine (CNIMI) sensitive and CNIMI resistant subclasses of platelet 3H-imipramine (3H-IMI) binding sites were studied in depressed patients and normal volunteers. Sinusoidal rhythms of the binding of both subclasses were found in patients and controls with peak levels in mid-February. Patient values of CNIMI sensitive binding fluctuated about a yearly average that was 32% lower than the average of controls. Patient deviations from the normal pattern were apparently bimodally distributed, whereas those of controls were normally distributed. CNIMI resistant binding was also normally distributed in controls, but not in depressed patients, although patient mesor values were not lower than those of controls. Platelet binding was not correlated with the severity of illness as measured by the Hamilton Rating Scale for Depression, and individual symptoms failed to discriminate between patients with high and low Bmax values.

Platelet tritiated imipramine binding in psychiatric patients: relationship to symptoms and severity of depression

The clinical and research significance of reduced imipramine binding has remained unclear despite considerable investigation. This study used an assay of demonstrated reliability to investigate the clinical correlates of imipramine binding to platelets in 63 depressed and 33 nondepressed psychiatric patients and 40 healthy control subjects. Both patient groups had Bmax values significantly lower than those of the healthy controls. Unequivocal associations between binding parameters and individual symptoms or groups of symptoms were not established, but a negative correlation between Kd and the number of adverse life events experienced in the preceding 6 months was apparent. These findings provide no support for the view that reduced binding is a trait marker for susceptibility to depression and cast doubt on its specificity as a state marker for the syndrome of depression.

Biogenic amines and their metabolites in body fluids of normal, psychiatric and neurological subjects

The biogenic monoamines and their metabolites have been isolated, identified and quantified in human body fluids over the past forty years using a wide variety of chromatographic separation and detection techniques. This review summarizes the results of those studies on normal, psychiatric and neurological subjects. Tables of normal values and the methods used to obtain them should prove to be useful as a reference source for benchmark amine and metabolite concentrations and for successful analytical procedures for their chromatographic separation, detection and quantification. Summaries of the often contradictory results of the application of these methods to psychiatric and neurological problems are presented and may assist in the assessment of the validity of the results of experiments in this field. Finally, the individual, environmental and the methodological factors affecting the concentrations of the amines and their metabolites are discussed.