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J Marcusson

Publications and source records attributed to J Marcusson.

At least 19 recordsLinked to original sources
PubMed2000

Selective effects on NGFI-A, MR, GR and NGFI-B hippocampal mRNA expression after chronic treatment with different subclasses of antidepressants in the rat.

There is a latency period of several weeks before the onset of clinical effect of antidepressant drugs. The detailed mechanisms underlying drug-induced adaptive neuronal changes are not known. To elucidate the involvement of changes in gene expression of candidate transcription factors, we treated rats for 21 days with buspirone, fluoxetine, 8-OH-DPAT and moclobemide. In situ hybridization was used to study mRNAs encoding NGFI-A, NGFI-B and the glucocorticoid receptors, MR and GR. NGFI-A mRNA expression increased profoundly in the hippocampal formation and the cerebral cortex after all drug treatments, especially after moclobemide treatment (77-122% increase); with the exception of buspirone. MR mRNA expression was induced in hippocampal CA1/CA2 subregions (27-37%) by all antidepressants, while moclobemide and 8-OH-DPAT significantly increased GR gene expression mainly in the CA1 region (31-44%). NGFI-B mRNA was significantly decreased in the hippocampal CA3 subfield (23%) and restrosplenial granular cortex (38%) by moclobemide treatment. There are selective effects of antidepressant drugs on specific transcription factors. These may be important for adaptive neuronal and neuroendocrine changes after antidepressant treatment including HPA axis negative feedback regulation.

Animals↗
PubMed1999

[3H]tiagabine binding to GABA uptake sites in human brain.

The binding of [3H]tiagabine ((RS-1-(4,4-(3-methyl-2-thienyl)-3-butenyl)-3-piperidine carboxylic acid) to homogenates of frozen post-mortem human brain has been characterized. Inhibition experiments with gamma-aminobutyric acid (GABA), GABA uptake inhibitors, ligands active at postsynaptic GABA receptors and receptors for other neurotransmitters, suggest that [3H]tiagabine binds with high affinity to GABA uptake sites. Inhibition and kinetic experiments suggests that 70%-80% of the binding is to a high affinity site. Saturation experiments showed that the binding was saturable. Bmax was 3.4 pmol/mg protein and Kd 16 nM in frontal cortex. The dissociation constants (Kd) measured in kinetic and equilibrium experiments were in the same range (16-56 nM). The regional distribution was studied in nine brain regions and the binding was heterogenous, with the highest binding in frontal cortex and parietal cortex and the lowest binding in nucleus caudatus and putamen. This is, to our knowledge, the first study on [3H]tiagabine binding in human tissue. It is concluded that [3H]tiagabine binding can be used as a specific marker for the GABA transporter GAT-1 in homogenates of human brain.

Adult↗
PubMed1999

GABA transporters (GAT-1) in Alzheimer's disease.

The presynaptically located gamma-aminobutyric acid (GABA) transporter (GAT-1) was studied in a group of patients with Alzheimer's disease (AD) and in a control group using the GAT-1 selective radioligand [3H]tiagabine. Post mortem brain tissue from frontal cortex, temporal cortex, and caudate nucleus from 18 AD patients and 23 age-matched controls were studied. The binding was saturable (Kd 26 nM) and region specific. There were no significant differences between the groups with respect to the binding capacity (Bmax) and binding affinity (Kd). The unaltered [3H]tiagabine binding to GAT-1 protein indicates that intrinsic GABA neurons are spared in Alzheimer's disease.

Aged↗
PubMed1998

Chronic amitriptyline treatment induces hippocampal NGFI-A, glucocorticoid receptor and mineralocorticoid receptor mRNA expression in rats.

Adult male rats were treated with the antidepressant drug amitriptyline for 21 days and the expression of specific transcription factors was examined. NGFI-A mRNA expression was increased in the hippocampus and in the cerebral cortex. MR mRNA was increased in the hippocampus while GR mRNA was increased in selective hippocampal regions. There was no change in the NGFI-B mRNA expression. Thus, NGFI-A may be a mediator of plasticity-related phenomena induced by antidepressant drugs.

Amitriptyline↗
PubMed1998

Associated physical disease in a demented population.

Clinical experience indicates that physical diseases are probably underdiagnosed in patients suffering from dementia. We investigated the prevalence of physical diseases in patients with different types of dementia by means of a retrospective patient record survey including 236 inpatients and outpatients referred for dementia evaluation to the Dementia Investigation Unit, University Hospital in Linköping during 1994. Forty-four patients had dementia of the Alzheimer type, 78 had vascular dementia, 28 had dementia due to multiple etiologies, 42 were not demented, and 44 patients could not be classified by the DSM IV criteria. The physical diseases were registered as separate diagnoses comprising all newly-diagnosed physical diseases and previously known diseases that had exacerbated and contributed to the medical contact. Sixty-four percent of the patients had previously unknown physical diseases and/or exacerbation of previously known diseases. The most common physical conditions were cobalamin deficiency and infectious diseases, which occurred in 27% and 24% of the patients, respectively. There was no difference in the number or kinds of diagnoses between the diagnostic groups. Associated physical diseases were underdiagnosed in patients referred for dementia evaluation. We suggest that thorough medical investigation and adequate treatment are of importance in the management of dementia.

Aged↗
PubMed1998

Characterization of the 5-HT4 binding site in human brain.

In this study, drug inhibition and saturation experiments on the binding of the highly selective 5-HT4 antagonist [3H]GR 113808 were performed in human brain membranes so as to better characterize this binding site. Drug competition studies were carried out by incubating 0.2 nM [3H]GR 113808 in the presence of increasing concentrations of six different drugs, i.e. 5-HT, 5-CT, ondansetron, tropisetron, BIMU 1 and BIMU 8 (mixed 5-HT3 and 5-HT4 agonists). The binding displaced by 5-HT showed a drug inhibition constant (Ki) value of 197nM. The use of 5-CT or ondansetron also showed the existence of single-site models albeit with Ki values in the micromolar range (11,5 microM). Tropisetron, BIMU 1 and BIMU 8 displaced bound [3H]GR 113808 according to a two-site binding model, with the high affinity component in the nanomolar range and the low affinity site in the micro or milimolar range. Saturation experiments revealed high binding densities in basal ganglia (187 fmol/mg in putamen, and 149 fmol/mg in caudate nucleus), while lower densities were observed in cortical regions (49 fmol/mg in temporal cortex, 45 fmol/mg in parietal cortex and 71 fmol/mg in cingulate cortex). The apparent affinity (Kd) was similar in the brain regions studied, ranging from 0.13 to 0.34 nmol/l. Despite the enrichment of 5-HT receptors in human brain, their functional correlate in brain diseases remains to be clarified.

Adult↗
PubMed1998

Propentofylline in the treatment of Alzheimer's disease and vascular dementia: a review of phase III trials.

Propentofylline, a neuroprotective glial cell modulator, has been shown in preclinical studies to address some of the common pathological processes of Alzheimer's disease (AD) and vascular dementia (VaD), including glial cell activation and increased production of cytokines, free radicals, and glutamate. To examine whether propentofylline (300 mg t.i.d. taken 1 h before meals) would provide beneficial effects in patients with AD and/or VaD, 901 patients with mild-to-moderate AD and 359 patients with mild-to-moderate VaD were enrolled in four double-blind, placebo-controlled, randomized studies ranging in duration from 6 months to 56 weeks. Propentofylline was found to provide consistent improvements over placebo in efficacy assessments for both AD and VaD patients. In addition, results from a drug withdrawal study suggested that propentofylline does not merely relieve dementia symptoms but slows the progression of the disease itself. Propentofylline had a good safety profile and was generally well tolerated.

Alzheimer Disease↗
PubMed1997

Serotonergic, noradrenergic, and dopaminergic measures in suicide brains.

Concentrations of the three main monoamines (5-HT, NA, and DA), their metabolites (5-HIAA, DOPAC, and HVA), and the serotonin precursor 5-hydroxy-L-tryptophan were simultaneously measured in frontal cortex, gyrus cinguli, and hypothalamus from 23 controls and 18 suicide victims. Overall suicides did not show significant differences with respect to the control group in any of the measured compounds. Significant increases in noradrenaline and dopamine concentrations were noted in the carbon monoxide poisoning suicides, together with a significant increased hypothalamic dopamine in the drug overdose suicides. It is suggested that the suicidal behavior is not related to substantial changes in cortical and hypothalamic monoaminergic function; however, the reported results could be secondary to the rapid effect of hypoxia and of the acute self-administration of certain drugs in specific metabolic pathways.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1997

GABA uptake sites in frontal cortex from suicide victims and in aging.

The binding of [3H]nipecotic acid to GABA uptake sites was studied in post mortem human frontal cortex from 17 suicide victims and 21 controls without known neurological or psychiatric disorder. The suicide victims were subclassified according to the use of violent or non-violent methods and to the presence or absence of a known history of a depressive disorder. No difference was found between the suicide victims and the controls with regard to [3H]nipecotic acid binding to GABA uptake sites (Bmax) and apparent affinity (Kd). No differences were found either with regard to method of suicide or whether a depressive symptom existed or not. The binding of [3H]nipecotic acid to GABA uptake sites was also studied in post mortem human frontal cortex with regard to aging. The age of the subjects ranged from 16 to 84 years. No significant difference in either Bmax or Kd was found. The present findings suggest that the GABA uptake sites in the human frontal cortex are not subjected to regulation or degenerative changes in conditions investigated.

Aged↗
PubMed1996

Brain monoaminergic and neuropeptidergic variations in human aging.

The effect of age on the monoamines 5-hydroxytryptamine (5-HT), noradrenaline (NA) and dopamine (DA), their metabolites 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), 3,4-dihydroxphenylacetic acid (DOPAC), and the 5-HT precursor 5-hydroxy-L-tryptophan (5-HTP), together with the peptides neuropeptide Y (NPY), somatostatin (SOM), and corticotropin-releasing factor (CRF), was studied in frontal cortex, gyrus cinguli and hypothalamus from 23 healthy control subjects, aged 16-75 years. After correcting for postmortem interval, significant decreases in gyrus cinguli NA, NPY and CRF, and hypothalamic DA, HVA, and 5-HIAA concentrations were obtained with advancing age. The involvement of the monoaminergic system in several functional abnormalities appearing in senescence is suggested. Furthermore, evidence is given of the participation of the peptidergic systems in the aging process.

Adolescent↗
PubMed1996

Diagnosis of dementia at the primary care level.

In Sweden, as in many other industrial countries, the majority of patients with symptoms of dementia are initially evaluated by a general practitioner (GP), and many do not receive a follow-up assessment by a specialist. Accordingly, GPs play a vital role in identifying patients with possible dementia and undertaking additional diagnostic procedures. Currently, however, the ability of most GPs to perform assessments for dementia is limited. It is important that tests to confirm the presence of dementia be performed uniformly, irrespective of the specialty of the examining physician. Once a diagnosis of dementia has been established and appropriate living arrangements for the patient have been made, the GP should continue to monitor the patient's health status. In Sweden, "dementia teams" of health care professionals have been successful in providing a consistently high level of care to patients with dementia, reducing the incidence of hospitalization for acute illness.

Dementia↗
PubMed1994

Brain 5-HT1A, 5-HT1D, and 5-HT2 receptors in suicide victims.

We report on 5-HT1A, 5-HT1D, and 5-HT2 binding sites in 23 control subjects and 18 suicide victims subdivided according to the method of death and the previous existence of depressive symptoms. No difference in maximum binding (Bmax) or binding affinity (Kd) was found between the control and overall suicide groups for the binding sites studied. The drug overdose subgroup showed, however, a significant decrease in the 5-HT1A binding affinity, probably explained by the higher sensitivity of this binding site to the acute administration of tricyclic antidepressants. A significant decrease in 5-HT1D binding affinity was also found in the depressed suicides, together with a significant decrease in the number of 5-HT1D binding sites in the nondepressed suicides. Further studies should be carried out on the 5-HT1D binding site as it might represent a new tool in the understanding of the depressive illness.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1994

[3H]paroxetine and [3H]citalopram as markers of the human brain 5-HT uptake site: a comparison study.

The binding of [3H]paroxetine and [3H]citalopram to the human brain serotonin (5-HT) uptake site has been characterized and compared. Our results reveal that the binding exclusively involved with the 5-HT uptake site is identical for both [3H]ligands. The selective 5-HT uptake inhibitor citalopram displays the highest affinity for this uptake site, as compared with the affinities obtained for desipramine and norzimeldine, which is in accordance with their respective blockage of 5-HT uptake. Similar Bmax values were obtained for both radioligands in the brain regions studied, indicating their binding to the same presynaptic membrane protein. Together these findings suggest that both [3H]paroxetine and [3H]citalopram are good markers of the 5-HT transporter as both bind selectively and with high affinity to the serotonin uptake sites. However, the higher affinity of [3H]paroxetine confirms that this compound is the best radioligand for the 5-HT uptake site available today.

Adult↗
PubMed1993

Effect of aging in human cortical pre- and postsynaptic serotonin binding sites.

5-HT1A, 5-HT1D, 5-HT2 binding sites and affinity and 5-HT uptake sites were simultaneously determined in frontal cortex samples from 23 control subjects, aged 16-75 years. A significant reduction in the number of 5-HT1D and 5-HT2 binding sites was found with regard to age, together with a significant decrease in the 5-HT2 binding affinity. It is suggested that the total 5-HT1 age-related loss described in previous studies could be ascribed to the 5-HT2 subtype. Furthermore, aging does not seem to be associated with a reduced cortical serotonergic innervation, as indicated by the stability of the [3H]paroxetine-labeled 5-HT uptake sites.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1992

[3H]nipecotic acid binding to GABA uptake sites in human brain.

The binding of [3H]nipecotic acid to frozen post-mortem human brain tissue has been characterized. Competition experiments with gamma-aminobutyric acid (GABA), GABA uptake inhibitors, ligands active at post-synaptic GABA receptors and receptors for other neurotransmitter systems, suggest that [3H]nipecotic acid binds to the neuronal (but not glial) GABA uptake site. Competition and kinetic experiments suggest that 85% of the binding is to a high affinity site. The dissociation constants (Kd) measured in kinetic and equilibrium experiments were in the same range (0.5-0.6 microM). The regional distribution was studied in 19 brain regions and the binding was relatively homogenous. It is concluded that [3H]nipecotic acid binding can be used as a marker for neuronal GABA uptake sites in post-mortem human brain tissue.

Aged↗
PubMed1992

Alterations in brain cholecystokinin receptors in suicide victims.

Cholecystokinin (CCK) and benzodiazepine receptor binding characteristics were analyzed in the brain tissue samples from 19 suicide victims and 23 control cases. In the frontal cortex, significantly higher apparent number of CCK receptors and affinity constants were found in the series of suicide victims. These differences between suicides and controls were present in similar proportions when the suicide cases with depressive syndrome or violent or non-violent means of self-killing were compared to matched controls. However, when the samples were split into subgroups consisting of persons either below or over the age of 60 years, significant differences in the CCK receptor characteristics in the frontal cortex were observed only between younger suicides and controls. Furthermore, the younger suicide victims had a higher density of CCK receptors in the cingulate cortex, whereas in older suicides the value was lower as compared to age-matched controls. No difference in benzodiazepine receptor binding was found between control and suicide groups. The results of this investigation suggest that CCK-ergic neurotransmission is linked to self-destructive behaviour, probably through its impact on anxiety and adaptational deficits.

Adolescent↗