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Biomedical subjects

D Naber

Publications and source records attributed to D Naber.

At least 109 records · Page 6Linked to original sources
PubMed1985

Neuroleptic withdrawal in chronic schizophrenia: CT and endocrine variables relating to psychopathology.

The psychopathology of 36 chronic, schizophrenic patients who had been on maintenance neuroleptics was rated during neuroleptic therapy and after 12 days of neuroleptic withdrawal. At both times, hormonal serum levels were also determined. Moreover, in 27 of these patients, ventricle-brain ratio, maximal width of the third ventricle, and sulcal widening were measured on computed tomography (CT). Neuroleptic withdrawal resulted in individually different psychopathological changes: 7 patients improved, 11 worsened. Within the whole group, thought disorder deteriorated, and anergia improved. Levels of cortisol and beta-endorphin increased; those of prolactin and norepinephrine decreased. The majority of patients showed ventricular enlargement, which was marginally related to reduced thought disorder. CT and endocrine variables were slightly related to psychopathology or psychopathological effects of neuroleptic withdrawal.

Adult↗
PubMed1985

Neuroendocrine and psychological variables relating to post-operative psychosis after open-heart surgery.

Post-operative psychosis is a frequent complication after open-heart surgery. To investigate relationships between psychopathological outcome and endocrine and psychological variables, serum levels of cortisol, beta-endorphin, norepinephrine, TSH, and cholesterol were measured in 23 male patients undergoing aortic valve replacement from the day before operation (OP) until the seventh day after OP. State and trait anxiety, stress appraisal and the use of coping styles also were assessed. After OP, eight patients suffered from post-OP psychosis and nine from minor psychopathological symptoms. Post-OP psychopathology was significantly correlated with pre-OP psychopathological score as well as with state anxiety, pre- and post-OP stress, and the use of a self-controlling coping style. Serum cortisol, beta-endorphin, norepinephrine, and TSH levels were markedly elevated after OP. Cholesterol levels showed a decline. With regard to endocrine variables, the eight psychotic patients did not differ from 15 non-psychotic subjects, but a subgroup of three major depressed patients had distinctly elevated levels of cortisol and norepinephrine. For all 23 patients, pre-OP cholesterol correlated with pre-OP psychopathology and post-OP depression. Furthermore, post-OP depression was significantly correlated with both post-OP cortisol and norepinephrine. These results indicate the stressful nature of the OP and suggest a multifactorial association of endocrine and psychological variables with psychiatric complications after open-heart surgery.

Adult↗
PubMed1984

Neuroendocrine effects of apomorphine in chronic schizophrenic patients under long-term neuroleptic therapy and after drug withdrawal: relations to psychopathology and tardive dyskinesia.

The sensitivity of the dopaminergic hypothalamic pituitary system, as indicated by growth hormone (GH) release after apomorphine (0.5 mg SC), was studied in 11 chronic schizophrenic in-patients under long-term neuroleptic (NL) therapy and after 12 and 30 days' drug withdrawal. GH peak levels after a 12-day drug-free period were significantly elevated (13.1 +/- 12 ng/ml) as compared to NL therapy (4.6 +/- 6.1 ng/ml). Controls showed a significant higher mean peak GH response (13.6 +/- 10 ng/ml) compared to chronic schizophrenic patients under long-term NL therapy. The GH response of patients with symptoms of tardive dyskinesia (TD) did not differ significantly from that of patients without signs of TD. The prolactin (PRL) serum levels under long-term NL treatment were within the normal range in male schizophrenics but decreased significantly after 12 days' drug withdrawal. The data presented indicate a reduced sensitivity of the hypothalamic-pituitary dopamine receptors under long-term NL therapy. The significant increase in GH response on day 12 probably corresponds to a readjustment from a mostly blunted GH response under NL therapy back to stimulated levels of normal controls. No supersensitivity of the pituitary dopamine receptors could be detected.

Adult↗
PubMed1984

Endocrine effects of the cold pressor test: relationships to subjective pain appraisal and coping.

Blood was drawn from 14 normal volunteers twice before, immediately after a 1-minute immersion of the nondominant hand in ice water (cold pressor test), and twice during recovery. Serum levels of beta-endorphin, cortisol, prolactin, growth hormone, and opioid activity were determined, and measures of subjective pain appraisal and coping styles were obtained. Cortisol was the only variable to show a significant increase as a function of noxious stimulation. Correlational analysis yielded relationships between neuroendocrine variables and subjective pain appraisal as well as coping styles, suggesting complex interactions between neuroendocrine and psychological processes in human pain.

Adult↗
PubMed1984

No correlation between neuroleptic-induced increase of beta-endorphin serum level and therapeutic efficacy in schizophrenia.

In 23 acute, unmedicated, schizophrenic patients, psychotic behaviour and beta-endorphin serum level were measured before and during four weeks of neuroleptic therapy. Prior to drug treatment, beta-endorphin level of all patients was within the normal range. Neuroleptic therapy induced marked elevations of beta-endorphin in eight subjects; statistical analysis revealed a slight but significant increase for the whole group. This endocrine effect was not correlated with therapeutic efficacy of neuroleptic treatment.

Adult↗
PubMed1983

Pain enhances naloxone-induced hyperalgesia in humans as assessed by somatosensory evoked potentials.

The effect of 8 mg IV naloxone on pain appreciation was studied with electric shocks administered to the left forearm of 20 normal volunteers. Pain sensitivity was assessed with a psychophysical task and with evoked potentials (EP) to the pain stimuli which were found sensitive to opiate agonists and antagonists in previous experiments. Naloxone-induced hyperalgesia before and after 20 min of intermittent shock was assessed in a 3-day placebo crossover experiment designed to provide control comparisons of time effects. EP amplitude enhancement with naloxone was significantly greater following 20 min of shocks than preceding them, while pain judgments were not significantly affected. Thus, naloxone increases pain sensitivity, especially after prolonged pain stimulation. This finding is consistent with endorphin mediation of stress-induced analgesia and raises the question of whether this type of response decrement over time is related to the phenomena of habituation.

Adult↗
PubMed1983

Circadian rhythms in rat brain neurotransmitter receptors.

In the rat brain there are daily rhythms in the number of alpha- and beta-adrenergic, muscarinic cholinergic, dopamine, opiate, and benzodiazepine receptors. The rhythms are circadian, i.e., with periods of approximately 24 h and endogenously generated. The characteristics of the circadian rhythms change over the year. Ablation of the suprachiasmatic nuclei, believed to act as a biological clock, abolishes the circadian rhythms. In the cerebral cortex the circadian rhythm in norepinephrine-stimulated cyclic AMP production is a biological response to the circadian rhythms in alpha- and beta-adrenergic receptors. The effects on neurotransmitter receptor rhythms of treatments that are antidepressant in humans were studied. Chronic administration of the antidepressant drugs imipramine and clorgyline delays the timing of the peak number of many receptors. Chronic administration of the antidepressant, antimanic drug lithium carbonate delays the timing of the peak number of some receptors and abolishes the rhythms in several others. Twenty-four hours of sleep deprivation is almost without effect on the rhythms. Fluphenazine and lithium, both antimanic in humans, increase the 24-h mean number of most receptors. Circadian receptor rhythms evoking intracellular circadian biological responses may modulate brain neurotransmission, coordinating internal physiological processes, and synchronizing them to environmental events. Alterations in circadian receptor rhythms with chronic psychoactive drug administration may play a role in the therapeutic actions of these drugs.

Animals↗
PubMed1983

The measurement of endorphins in body fluids.

The measurement of endorphins in body fluids has been an important advance in clinical research attempting to link the endogenous opioid system to psychiatric illness and symptomatology. The consideration of methodologic differences in assay technique and in clinical methods is important in evaluating results of studies. Whereas findings in early clinical studies supported the notion of increased endorphin system function in patients with schizophrenia, cumulative data from the considerable number of studies carried out throughout world centers have been unable to demonstrate a consistent abnormality in levels of endorphins in CSF or plasma of patients with schizophrenia. Among the affective disorders, data suggest the possibility of relative changes in levels of opioids within individual manic-depressive patients when studied across state change from depression to mania. In studies of depressive illness there is accumulating evidence that the endogenous opioid system may relate or contribute to abnormality of the HPA axis. In our work measuring opioids in CSF we have observed relationships between anxiety and CSF opioids in normals and psychiatric patients and changes in CSF opioid activity in patients with anorexia nervosa accompanying weight change. These data are consistent with other evidence linking endorphins to CNS noradrenergic systems and to biologic response to stress.

Anorexia Nervosa↗
PubMed1982

Effects of chronic lithium, clorgyline, imipramine, fluphenazine and constant darkness on the alpha-melanotropin content and circadian rhythm in rat brain.

The effects of constant darkness, chronic lithium, clorgyline, imipramine and fluphenazine treatment on the content and diurnal rhythm of alpha-MSH in rat forebrain were investigated. The persistence of the alpha-MSH rhythm in constant darkness demonstrated that the rhythm was circadian in nature. Constant darkness increased the 24 h mean alpha-MSH concentration in brain while lithium, fluphenazine and imipramine decreased it. In addition, imipramine and clorgyline delayed the phase of the alpha-MSH circadian rhythm while lithium advanced it.

Animals↗
PubMed1982

Clorgyline delays the phase-position of circadian neurotransmitter receptor rhythms.

The number of alpha- and beta-adrenergic, muscarinic cholinergic, opiate, and benzodiazepine receptors in rat forebrain, and dopamine and benzodiazepine receptors in striatum, change throughout the day. The diurnal rhythms of these receptors were altered by treatment with the monoamine-oxidase inhibitor clorgyline: following treatment some or all rhythm characteristics of wave form, amplitude, 24-h mean, and phase, were affected. One common effect of treatment was a delay in phase-position of binding to alpha- and beta-adrenergic, opiate and benzodiazepine receptors. Additionally, the nocturnal elevation in pineal melatonin which normally returns to baseline at light onset, persisted 3 h into the light period after clorgyline administration. These biochemical observations extend behavioural findings that clorgyline can delay the phase-position of rodent nocturnal activity onset, and does so by slowing the central circadian pacemaker.

Animals↗
PubMed1982

Response of plasma beta-endorphin immunoreactivity to d-amphetamine and placebo in schizophrenic patients.

The response of plasma beta-endorphin (ir) to infusions of randomly assigned d-amphetamine (20 mg) and placebo was studied in eight schizophrenic patients. Although there was no statistically significant difference between the response to d-amphetamine and placebo, significant increases in plasma beta-endorphin (ir) levels were observed following each infusion. Although heterogeneity in beta-endorphin (ir) response was observed, individual differences did not relate to clinical variables such as abnormalities on computed tomography or "process-reactive" distinctions. An excessive beta-endorphin response to placebo in schizophrenia is discussed.

Adult↗