Search results for "DOPAMINE"
showing 10 items of 660 documents
Apomorphine-Induced Growth Hormone Response Is Attenuated by Ethanol but Not Dextromethorphan
2007
Background: Misuse of alcohol drinking is a major health problem. Alcohol decreases spontaneous growth hormone (GH) secretion, but the mechanism is unclear. The aim of this study was to test whether administration of alcohol (study 1) or a N-methyl d-aspartate (NMDA) receptor antagonist (study 2) attenuates the GH response to pharmacological dopaminergic stimulation. Methods: The 2-session repeated measures design was conducted at the endocrine laboratory at the Department of Psychiatry at the Free University Berlin. Twenty healthy Caucasian males aged 35±10 years without a history of alcohol use disorders were tested using the Apomorphine (APO) challenge test. In study 1, we injected APO (…
Reward anticipation revisited- evidence from an fMRI study in euthymic bipolar I patients and healthy first-degree relatives.
2017
Abstract Background Symptomatic phases in bipolar disorder (BD) are hypothesized to result from a hypersensitive behavioral activation system (BAS) being sensitive to potential rewards. However, studies on the neuronal underpinnings of reward anticipation in BD are scarce with contradictory findings and possibly confounded by effects of dopaminergic medication, necessitating further research on dysfunctional motivation in BD. Moreover, its role as vulnerability marker for BD is unclear. Methods Functional imaging was conducted in 16 euthymic BD-I patients free from dopaminergic medication and 19 healthy first-degree relatives using a monetary incentive delay task and compared to parallelize…
[123I]IBZM SPECT in patients treated with typical and atypical neuroleptics: relationship to drug plasma levels and extrapyramidal side effects
1997
[123I]Iodobenzamide (IBZM) is an iodine-labeled dopamine receptor ligand and can be used to visualize brain D2 receptors in humans with single photon emission computerized tomography (SPECT). The ratio of striatal IBZM uptake to uptake in frontal cortex (ST/FC ratio) represents a semiquantitative measure of D2 receptor binding in the striatum. Our study sample included six patients treated with haloperidol (3.0-8.0 mg/day orally; one patient with an average of 0.9 mg/day intramuscularly), five patients with benperidol (9.0-15.0 mg/day orally) and nine patients treated with clozapine (200.0-600.0 mg/day orally). Typical neuroleptics (TNs) and atypical neuroleptics (ANs) were significantly di…
Adult attachment and gene polymorphisms of the dopamine D4 receptor and serotonin transporter (5-HTT).
2010
Recently, the Dopamine D4 Receptor Gene (DRD4) and the Serotonin Transporter Gene (5-HTT) have been found to be candidate genes for infant attachment disorganization. The present study aimed to explore the relationship of these genes to adult attachment representations. The Adult Attachment Interview was used to assess attachment representations in 167 German adults. DNA from buccal cells was genotyped for the DRD4 VNTR Exon III and 5-HTT LPR polymorphisms with respect to the presence of the 7repeat allele and the short allele, respectively. DRD4 7repeat allele carriers were significantly more likely to be securely attached than those without 7repeat but only for subjects with unloving care…
Baseline [18F]-FDOPA kinetics are predictive of haloperidol-induced changes in dopamine turnover and cognitive performance: A positron emission tomog…
2007
The telencephalic dopamine innervations contribute to the modulation of cognitive processing. However, the relationship between cognitive effects of D(2/3)-receptor antagonism and dopamine transmission is not described in healthy subjects. We therefore tested effects of acute haloperidol (5 mg/d over 3 days) on continuous performance task (CPT) performance and 6-[(18)F]-fluoro-l-DOPA (FDOPA) PET parameters. Nine physically and mentally healthy male men performed two FDOPA-PET scans including arterial plasma withdrawal. Over 3 days before the second scan, all subjects were treated with 5 mg/d haloperidol orally. Using our novel steady-state analysis, we calculated the intrinsic rate of the c…
Relationship between dopamine D2 receptor occupancy, clinical response, and drug and monoamine metabolites levels in plasma and cerebrospinal fluid. …
2009
Combining measurements of the monoamine metabolites in the cerebrospinal fluid (CSF) and neuroimaging can increase efficiency of drug discovery for treatment of brain disorders. To address this question, we examined five drug-naive patients suffering from schizophrenic disorder. Patients were assessed clinically, using the Positive and Negative Syndrome Scale (PANSS): at baseline and then at weekly intervals. Plasma and CSF levels of quetiapine and norquetiapine as well CSF 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindole-acetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) were obtained at baseline and again after at least a 4 week medication trai…
Therapeutic drug monitoring for optimizing amisulpride therapy in patients with schizophrenia.
2005
Amisulpride is a clinically effective antipsychotic drug in a broad dose range with low propensity for extrapyramidal symptoms (EPS). Daily doses and plasma levels of amisulpride were analyzed within a large-scale therapeutic drug monitoring (TDM) survey to find plasma level ranges for optimized treatment under naturalistic conditions. Data of 378 schizophrenic patients treated with amisulpride (100-1550 mg) were included (40% female). Amisulpride plasma levels were analyzed at steady state; assessment comprised improvement (CGI-I) and side-effects, particularly EPS. For detection of cut-off values regarding non-response or EPS, receiver operating characteristics (ROC) curves were applied a…
Striatal and extrastriatal D2/D3-receptor-binding properties of ziprasidone: a positron emission tomography study with [18F]Fallypride and [11C]raclo…
2008
To elucidate the Batypicality( of ziprasidone, its striatal and extrastriatal D2/D3-receptor binding was characterized in patients with schizophrenia under steady-state conditions. These data were compared with striatal receptor occupancy values after single-dose ziprasidone ingestion in healthy controls. ( 18 F)fallypride positron emission tomography (PET) recordings were obtained in 15 patients under steady-state ziprasidone treatment at varying time points after the last dose. Binding potentials were calculated for striatal and extrastriatal regions. D2/D3-receptor occupancies were expressed relative to binding potentials in 8 unmedicated patients. In a parallel ( 11 C)raclopride-PET stu…
Evidence for the importance of the human dopamine transporter gene for withdrawal symptomatology of alcoholics in a German population
2002
Two new polymorphisms in the 3' untranslated region (3'UTR) of the dopamine transporter (DAT1) gene, adjacent to the known variable number of tandem repeats (VNTR) polymorphism, have been investigated in the present population-based association study including 351 alcoholics and 336 controls. The DraI restriction site was not polymorphic in our population. The G2319A polymorphism was not significantly different with respect to genotype or allele distribution between alcoholics and controls. Subsequently, in individuals with VNTR homozygosity for the ten repeat allele, we found a higher prevalence of A/A homozygosity in patients with seizure history (P = 0.001, odds ratio (OR) = 7.913), with…
Dopamine D4 receptor exon III polymorphism, adverse life events and personality traits in a nonclinical German adult sample.
2010
Personality and temperament embrace a wide area of both psychological and behavioral processes which are also based on disposition. A functional polymorphism in exon III of the dopamine D4 receptor gene (DRD4) has been a highly suspect genetic marker for personality in spite of ambiguous results. The present study aimed to further elucidate the relationship between DRD4, negative life events and personality in a representative nonclinical sample. Hundred sixty-seven Germans completed the NEO Five-Factor Inventory, the Tridimensional Personality Questionnaire and the California Adult Q-Sort. A factor analysis revealed 3 factors: emotional stability, social orientation and impulsivity. DNA fr…