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Biomedical subjects

D Naber

Publications and source records attributed to D Naber.

144 records · Page 8Linked to original sources
PubMed1980

Dopamine receptor binding in rat striatum: ultradian rhythm and its modification by chronic imipramine.

To investigate diurnal variations in dopamine receptor binding, the amount of specifically bound 3H-spiroperidol was measured at 4-h intervals over a 24-h period in the striatum of rats which had been housed under a controlled 12-h light-dark cycle (lights on 7 a.m.). A highly significant ultradian rhythm with peaks at 2 a.m. and 2 p.m. was found with an amplitude of about 75%. Chronic imipramine modified the rhythm such that the two peaks occurred 4 h later and amplitude as well as 24-h mean of binding decreased. Scatchard analysis at times of least and greatest binding indicated that the differences in binding were due not to changes in the affinity, but in the number of binding sites. These results are interpreted with regard to the mode of action of psychoactive drugs and to postulated changes of receptor sensitivity in neurological and psychiatric disorders.

Animals↗
PubMed1980

Basal and stimulated levels of prolactin, TSH and LH in serum of chronic schizophrenic patients, long-term treated with neuroleptics.

Basal and stimulated (0.2 mg TRH, 0.025 mg LHRH) levels of prolactin, TSH and LH were measured in serum of 12 male and 10 female chronic schizophrenic patients, hospitalized and treated with neuroleptics from 6-21 years. The mean values of the 3 pituitary hormones were within the normal range in both sexes. Tolerance to the prolactin increasing effect of neuroleptics appears to develop after long-term neuroleptic treatment. TSH and LH secretion are not markedly impaired by chronic neuroleptic treatment.

Adult↗
PubMed1980

Effect of long-term neuroleptic treatment on prolactin and norepinephrine levels in serum of chronic schizophrenics: relations to psychopathology and extrapyramidal symptoms.

The estimation of serum prolactin (Prl) and norepinephrine (NE) in chronic schizophrenics treated with neuroleptics for 5-25 years showed no elevated Prl levels in either men or women (4.9 +/- 4.1 and 13.7 +/- 12.1 ng/ml, respectively). No significant correlation to duration or dosage of neuroleptic treatment, psychopathological syndromes and occurrence of tardive dyskinesia or parkinsonian side effects could be seen. The development of tolerance of the tuberoinfundibular dopamine system is discussed. The NE levels were distinctly elevated in both sexes; in men up to 0.77 +/- 0.4 and in women up to 0.90 +/- 0.48 ng/ml. This elevation is induced rather by neuroleptic treatment than by external factors. A significant relationship between dosage or duration of anticholinergic treatment and the severity of tardive dyskinesia was found in men.

Adult↗
PubMed1980

Basal and stimulated levels of prolactin, TSH, and LH in serum of chronic schizophrenic patients long-term treated with neuroleptics: relations to psychopathology.

Basal and stimulated (0.2 mg TRH, 0.025 mg LHRH) levels of prolactin, TSH, and LH were measured in serum of 12 male and 10 female chronic schizophrenic patients, hospitalized and treated with neuroleptics from 6 to 21 years. The mean values of the three pituitary hormones were within the normal range in both sexes. Tolerance to the prolactin-increasing effect appears to be developed after long-term neuroleptic treatment; TSH and LH secretion are not markedly impaired. The severity of psychopathological syndromes failed to correlate with serum levels of prolactin, TSH, and LH.

Adult↗
PubMedDate not supplied

Opiate receptor sensitivity in depressed patients before and after clomipramine treatment.

To measure opiate receptor sensitivity, the effects of naloxone on beta-endorphin and cortisol serum levels were determined before and after 3 weeks of clomipramine treatment (75 mg/day i.v.) in 12 patients with major depressive disorder. The opiate antagonist significantly increased both hormonal levels. The only significant endocrine differences between pre- and post-treatment were basal and maximal cortisol levels, which were elevated before antidepressant therapy. The rise in the cortisol or beta-endorphin serum level after naloxone injection was not affected by clomipramine treatment. There was no significant relationship between depression score and basal or stimulated endocrine variables. These data do not indicate a distinct effect of antidepressants on opiate receptor sensitivity.

Adult↗
PubMedDate not supplied

Subjective cognitive dysfunction in first-episode and chronic schizophrenic patients.

Previous studies indicate that first-episode and chronic schizophrenic patients do not differ regarding neuropsychological performance as assessed with standard cognitive tasks. For the present study, it was investigated whether first-episode and chronic schizophrenics report similar subjective cognitive deficits. The Frankfurt Complaint Questionnaire (FCQ), a scale devised for assessing subjective cognitive disturbances in schizophrenia, was administered to 20 first-episode and 36 chronic schizophrenic patients, as well as 20 healthy controls. The schizophrenic subsamples did not differ on any of the FCQ subscales or on a "lie scale," measuring illness denial. Psychopathological ratings were comparable for both groups. As expected, healthy subjects reported significantly less cognitive and perceptual problems than schizophrenic patients. In marked contrast to a Kraepelinian view of schizophrenia, the present data confirm previous studies conducted with objective neuropsychological tests that schizophrenia is a neurodevelopmental rather than a neurodegenerative disorder.

Adult↗
PubMedDate not supplied

Protein and nucleic acid content in the aging human brain.

The frontal cortex, white matter, cerebellum, caudate nucleus, thalamus and putamen of human brains, ranging from 16 to 91 years, were assayed for protein and nucleic acids. In all these areas the protein content decreased by 5--15% between 30 years and 90 years-of-age. The nucleic acid content, however, did not show any significant change. During a post-mortem interval of 6--25 hours there was no significant decrease found in either the protein or the nucleic acid content of brain tissue.

Adolescent↗
PubMedDate not supplied

Cognitive dysfunction at baseline predicts symptomatic 1-year outcome in first-episode schizophrenics.

The present study addresses the consequences of cognitive disturbances on symptomatic outcome. Fifty-three first-episode schizophrenics were reassessed (n = 32) 1 year after admission. Simple regression analyses revealed that several self-perceived cognitive deficits at baseline as measured with the Frankfurt Complaint Questionnaire significantly predicted increased Brief Psychiatric Rating Scale global scores at follow-up (p = 0.05 to p = 0.005). A stepwise regression analysis proved memory dysfunction to be the strongest predictor of symptomatic worsening (p = 0.005). It is suggested that the exploration and treatment of neuropsychological deficits in schizophrenia is of great clinical importance with regard to its impact on both functional and symptomatic outcome in schizophrenia.

Acute Disease↗