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1.
J Cell Biol ; 53(3): 654-61, 1972 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-4402165

RESUMO

A bulk fraction enriched with respect to neuronal cell bodies was used as starting material for the isolation of neuronal plasma membrane The cells were gently homogenized in isotonic sucrose and a crude membrane containing fraction sedimented at 3000 g. Subsequently, the membrane fraction was purified on a discontinuous sucrose density gradient between 35% and 25 5% sucrose (w/w). Enzymatic analyses showed a 4-5-fold enrichment in plasma membrane markers, and a 10-15% contamination of mitochondrial and microsomal material. Electron micrographs of the membrane fraction confirmed the enzymatic data Fragmented membranes were found, mainly in vesicular form No ribosomes, but a few mitochondria and some multilamellar membranes were seen


Assuntos
Membrana Celular , Neurônios/citologia , Adenosina Trifosfatases/análise , Animais , Fracionamento Celular , Membrana Celular/enzimologia , Nucléolo Celular , Núcleo Celular , Centrifugação com Gradiente de Concentração , Córtex Cerebral/citologia , Córtex Cerebral/enzimologia , Citocromos , Complexo IV da Cadeia de Transporte de Elétrons/análise , Glucofosfatos/análise , Métodos , Microscopia Eletrônica , Microssomos/enzimologia , Mitocôndrias/enzimologia , Monoaminoxidase/análise , NADP , Neurônios/enzimologia , Oxirredutases/análise , Coelhos , Sacarose
2.
Neurochem Res ; 34(9): 1584-93, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19288275

RESUMO

Mood disorders have been linked to glial and synaptic pathology such as disturbed neurotransmission of gamma-aminobutyric acid (GABA). We evaluated the expression of GABAergic marker genes in rats with helpless behaviour, an animal model of depression. Male Sprague-Dawley rats from inbred lines were tested for helpless behaviour and grouped according to failures in terminating foot shock currents. Expression levels of GABAergic marker genes were assessed using semiquantitative in situ-hybridization. Animals with congenital helpless behaviour (cH) were unable to escape current exposure in contrast to cH-animals derived from the same litters with low failure rates and to non-helpless animals (cNH). We found a significant downregulation of the GABA transporter GAT3 in cLH rats. GAT1 showed small changes, glutamic acid decarboxylase (GAD67) and the vesicular GABA transporter were not significantly altered. Reduced GABA transporter expression is well in concert with the behavioural phenotypes of knockout animals and strengthens the hypothesis of impaired glial functions in depression.


Assuntos
Depressão/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/biossíntese , Desamparo Aprendido , Ácido gama-Aminobutírico/fisiologia , Animais , Depressão/genética , Regulação para Baixo , Masculino , Ratos , Ratos Sprague-Dawley
3.
Arch Gen Psychiatry ; 37(10): 1160-3, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7425800

RESUMO

We examined the subsequent criminal activities of delinquent boys classified as having either socialized conduct disorder, undersocialized conduct disorder, aggressive type, or undersocialized conduct disorder, unaggressive type. A follow-up study of more than ten years revealed profound differences in the likelihood of criminal convictions or incarcerations between socialized and undersocialized delinquents. The socialized delinquents have less chance of being either convicted of a crime or being imprisoned. This difference supports the previous studies that demonstrated that these classifications could be distinguished on the basis of differences in behavior, personality, psychological test results, and characteristic family backgrounds, and reinforces this method of classifying conduct disorders. Differences between the undersocialized aggressive and unaggressive groups appear qualitative and indicate that subjects in the former group are involved in more crimes of violence subjects in the latter.


Assuntos
Crime , Delinquência Juvenil/psicologia , Socialização , Adolescente , Agressão , Transtorno da Personalidade Antissocial/psicologia , Transtornos do Comportamento Infantil/diagnóstico , Psicologia Criminal , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Transtornos do Comportamento Social/psicologia
4.
Arch Gen Psychiatry ; 57(10): 937-43, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11015811

RESUMO

BACKGROUND: We monitored the effect of electroconvulsive therapy (ECT) on the nuclear magnetic resonance-detectable metabolites N-acetylaspartate, creatine and phosphocreatine, and choline-containing compounds in the hippocampus by means of hydrogen 1 magnetic resonance spectroscopic imaging. We hypothesized that if ECT-induced memory deterioration was associated with neuronal loss in the hippocampus, the N-acetylaspartate signal would decrease after ECT and any increased membrane turnover would result in an increase in the signal from choline-containing compounds. METHODS: Seventeen patients received complete courses of ECT, during which repeated proton magnetic resonance spectroscopic imaging studies of the hippocampal region were performed. Individual changes during the course of ECT were compared with values obtained in 24 healthy control subjects and 6 patients remitted from major depression without ECT. RESULTS: No changes in the hippocampal N-acetylaspartate signals were detected after ECT. A significant mean increase of 16% of the signal from choline-containing compounds after 5 or more ECT treatments was observed. Despite the mostly unilateral ECT application (14 of 17 patients), the increase in the choline-containing compound signal was observed bilaterally. Lactate or elevated lipid signals were not detected. All patients showed clinical amelioration of depression after ECT. CONCLUSIONS: Electroconvulsive therapy is not likely to induce hippocampal atrophy or cell death, which would be reflected by a decrease in the N-acetylaspartate signal. Compared with an age-matched control group, the choline-containing compounds signal in patients with a major depressive episode was significantly lower than normal, before ECT and normalized during ECT.


Assuntos
Ácido Aspártico/análogos & derivados , Eletroconvulsoterapia , Hipocampo/anatomia & histologia , Hipocampo/metabolismo , Espectroscopia de Ressonância Magnética , Adulto , Ácido Aspártico/química , Ácido Aspártico/metabolismo , Morte Celular , Colina/análise , Colina/metabolismo , Creatina/análise , Creatina/metabolismo , Feminino , Hipocampo/química , Humanos , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Masculino , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Transtornos da Memória/metabolismo , Pessoa de Meia-Idade , Fosfatidilcolinas/análise , Fosfatidilcolinas/metabolismo , Fosfocreatina/análise , Fosfocreatina/metabolismo
5.
Biol Psychiatry ; 45(6): 737-42, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10188003

RESUMO

BACKGROUND: A significant increase in the [Ca2+]i response of single T lymphocytes to mitogenic stimulation with phytohemagglutinin is reported for 27 Alzheimer patients compared with 27 healthy gender- and age-matched control subjects, regardless of gender. METHODS: The [Ca2+]i signals of T lymphocytes were assessed using the Fura-2-AM method. RESULTS: In Alzheimer's disease (AD) the reaction pattern is similar to that seen in a group of 27 young healthy control subjects who exhibited a marked [Ca2+]i rise after stimulation. During normal aging the reaction pattern of T cells is significantly attenuated in comparison to that found in young subjects. In healthy control subjects differences in age-related changes in calcium homeostasis are highly significant among women, young women showing the most intense cell response. CONCLUSIONS: The elevation of [Ca2+]i appears to be a prerequisite for apoptosis, which is suggested to be involved in the neuronal death occurring in AD. An increased [Ca2+]i in AD is consistent with processes leading to neurodegeneration in AD.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/metabolismo , Cálcio/metabolismo , Linfócitos T/metabolismo , Adulto , Idoso , Morte Celular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitógenos/farmacocinética , Neurônios/metabolismo , Fito-Hemaglutininas/farmacocinética
6.
Biol Psychiatry ; 29(2): 159-75, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1995085

RESUMO

Brain morphology was examined using magnetic resonance imaging in 30 first-episode patients with a schizophreniclike psychosis, 15 chronic schizophrenics, and 20 neurological controls. Statistical analyses of computer-generated measurements of regions of interest were controlled for gender, age, social class, and total brain volume. Lateral ventricular size was increased in both first-episode and chronic schizophrenic patients, with greater significance on the left than on the right side. Only the chronic patients, however, had reduced temporal lobe size, which also was greater on the left side. No major correlations of regional brain morphological measurements with cognitive functioning were found, although some measurements of verbal memory were correlated with parahippocampal size. This is a report of a preliminary study that suggests that some morphological brain changes may be present at the time of first treatment for a psychotic illness, whereas others may occur later in the course of illness. Future prospective studies may determine the clinical significance of these changes and whether they progress with the development of illness chronicity.


Assuntos
Encéfalo/anatomia & histologia , Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico , Adolescente , Adulto , Fatores Etários , Ventrículos Cerebrais/anatomia & histologia , Criança , Doença Crônica , Feminino , Lateralidade Funcional , Humanos , Masculino , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/diagnóstico
7.
Biol Psychiatry ; 50(10): 809-12, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11720700

RESUMO

BACKGROUND: In view of the effects of stress on synaptic plasticity, the regulation of synaptophysin and synaptotagmin expression by immobilization was analyzed by in situ hybridization. METHODS: Rats were exposed to immobilization stress, which induced typical behavioral alterations, such as reduced locomotor activity after stress exposure. Determination of mRNA levels of the integral synaptic vesicle proteins was performed immediately after acute or chronic immobilization. RESULTS: The results demonstrate that stress exposure leads to reduced expression of synaptophysin but increased expression of synaptotagmin in the hippocampus. CONCLUSIONS: This rapid and differential regulation of synaptic vesicle proteins could be responsible for some of the morphological, biochemical, and behavioral changes observed after stress exposure. These changes may be relevant to such clinical disorders as psychoses, depression, and posttraumatic stress disorder that are sensitive to stress and involve changes in neural and synaptic plasticity.


Assuntos
Proteínas de Ligação ao Cálcio , Hipocampo/patologia , Glicoproteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Estresse Psicológico/complicações , Sinaptofisina/genética , Animais , Regulação da Expressão Gênica/fisiologia , Plasticidade Neuronal/genética , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Restrição Física , Estresse Psicológico/patologia , Sinaptotagminas
8.
Am J Psychiatry ; 139(12): 1601-3, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7149061

RESUMO

Modified leukotomies were performed on 5 patients with severe, incapacitating obsessional neurosis. Symptoms had been present for 6 or more years in all patients, and 3 had been ill for more than 20 years. All had received adequate trials of more conventional treatments before the leukotomy but had shown little response. At the time of follow-up, which range from as early as 1 year to as late as nearly 7 years after surgery, each patient's condition had improved. One was considered to be in "full remission," there were "much improved," and one was still symptomatic but "improved."


Assuntos
Transtorno Obsessivo-Compulsivo/cirurgia , Psicocirurgia/métodos , Adulto , Feminino , Seguimentos , Giro do Cíngulo/cirurgia , Humanos , Transtorno Obsessivo-Compulsivo/psicologia
9.
Am J Psychiatry ; 134(5): 556-8, 1977 May.
Artigo em Inglês | MEDLINE | ID: mdl-557905

RESUMO

The authors examined the records of 127 female and 1,068 male offenders referred by the courts to a forensic service over a 22-year-period. Female offenders were less likely than male offenders to be referred for psychiatric evaluations when they were charged with criminal behavior. They were more likely to be charged with homicide, arson, forgery, or fraud and more frequently received diagnoses of affective disorder and neurosis.


Assuntos
Psicologia Criminal , Psiquiatria Legal , Transtornos Mentais/epidemiologia , Sintomas Afetivos/epidemiologia , Piromania , Homicídio , Humanos , Histeria/epidemiologia , Missouri , Transtornos Neuróticos/epidemiologia , Esquizofrenia/epidemiologia , Fatores Sexuais , Controle Social Formal , Violência
10.
Am J Psychiatry ; 133(6): 694-6, 1976 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1275101

RESUMO

The authors examined records of 239 individuals charged with sexual offenses and referred by the courts to a forensic service. Defendants charged with rape were typically under 30 with histories of antisocial behavior that included other types of violence. Major mental illness was rare in this group. Child molesters in the sample were of no particular age, usually had no history of violent behavior, and had a low incidence of psychosis. The most common secondary diagnosis in both groups was alcohol or drug abuse.


Assuntos
Psiquiatria Legal , Transtornos Mentais/diagnóstico , Delitos Sexuais , Alcoolismo/diagnóstico , Humanos , Transtornos Parafílicos/complicações , Pedofilia/complicações , Pedofilia/diagnóstico , Estupro , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
11.
Am J Psychiatry ; 158(8): 1314-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11481168

RESUMO

OBJECTIVE: Using proton magnetic resonance spectroscopic imaging, the authors measured thalamic N-acetylaspartate (NAA) concentrations in patients with schizophrenia. METHOD: The study included 15 schizophrenic patients on a stable medication regimen and 15 age-matched healthy comparison subjects. Concentrations of NAA, creatine plus phosphocreatine, and choline-containing compounds in bilateral thalamic regions were determined. RESULTS: Previous findings of lower NAA concentration in the left and right mediodorsal region of the thalamus and significant correlations between left and right thalamic NAA measures in patients with schizophrenia were corroborated. Furthermore, the concentrations of choline-containing compounds were significantly lower in the schizophrenic patients. No group differences in creatine plus phosphocreatine were found. CONCLUSIONS: There is strong evidence for neuronal dysfunction or loss in the mediodorsal region of the thalamus in patients with schizophrenia.


Assuntos
Ácido Aspártico/análise , Esquizofrenia/diagnóstico , Tálamo/química , Adulto , Ácido Aspártico/análogos & derivados , Colina/análise , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Masculino , Fosfocreatina/análise , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Tálamo/fisiopatologia
12.
Neuropharmacology ; 30(1): 101-5, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2046876

RESUMO

After exposure to a 0.8 mA course of uncontrollable shocks, Sprague-Dawley rats can be differentiated into two distinct groups defined in term of their performance in a shock escape paradigm. Learned helpless (LH) rats do not learn to escape a controllable shock while non-helpless (NLH) rats learn this response as quickly as naive controls (NC) rats do. The current experiments were designed to extend our studies of 5-HT receptors in these three groups of rats. The major finding in the present study concerned post-synaptic 5-HT receptor effects in the cortex, hippocampus, septum and hypothalamus of LH rats. These included an up regulation of 5-HT1b receptors in the cortex, hippocampus and septum in LH rats. In contrast, 5-HT1b receptors in the hypothalamus of LH rats were down-regulated. These results implicate serotonergic mechanisms in the behavioral deficit caused by uncontrollable shock with a limbic-hypothalamic circuit serving as a center for adaptation to stress.


Assuntos
Encéfalo/metabolismo , Depressão/fisiopatologia , Desamparo Aprendido , Receptores de Serotonina/metabolismo , Animais , Córtex Cerebral/metabolismo , Depressão/metabolismo , Modelos Animais de Doenças , Eletrochoque , Reação de Fuga , Hipocampo/metabolismo , Hipotálamo/metabolismo , Cinética , Masculino , Ratos , Ratos Endogâmicos , Valores de Referência
13.
Neuropharmacology ; 31(4): 323-30, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1387924

RESUMO

After exposure to uncontrollable shock training, two distinct groups of rats can be defined in terms of their performance in learning to escape from a controllable stress. Learned helpless rats do not learn to terminate the controllable stress, whereas non-learned helpless rats learn this response as readily as naive control rats do. The present studies were designed to examine the correlations between the behavioral differences and the changes of presynaptic serotonergic activity, seen in these groups of rats. The major findings concerned presynaptic serotonergic effects in the hippocampus and hypothalamus of learned helpless rats. In the hippocampus, these included a statistically significant increase in three presynaptic 5-hydroxytryptamine (5-HT) mechanisms: K(+)-induced release of [3H]serotonin, high affinity uptake of [3H]serotonin and maximum density of binding sites for uptake of 5-HT, measured with [3H]paroxetine. In the hypothalamus, there was a differential modulation of all three presynaptic 5-HT mechanisms. A significant decrease in: K(+)-induced release of [3H]serotonin, in high affinity uptake of [3H]serotonin and the maximum binding site density of [3H]paroxetine binding was observed. No changes in uptake site binding was seen in other regions of the brain examined. These results implicate presynaptic serotonin mechanisms in the behavioral deficit caused by uncontrollable shock. In addition, a limbic-hypothalamic pathway may serve as a control center for the behavioral response to stress.


Assuntos
Encéfalo/metabolismo , Eletrochoque , Reação de Fuga , Serotonina/metabolismo , Estresse Psicológico/fisiopatologia , Sinapses/fisiologia , Análise de Variância , Animais , Transporte Biológico , Desamparo Aprendido , Hipocampo/metabolismo , Hipotálamo/metabolismo , Técnicas In Vitro , Masculino , Modelos Psicológicos , Paroxetina , Piperidinas/metabolismo , Potássio/farmacologia , Ratos , Ratos Endogâmicos , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/metabolismo , Sinapses/efeitos dos fármacos
14.
Pharmacogenomics ; 1(1): 63-71, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11258598

RESUMO

Different gene variants have been identified as risk or protective factors in alcoholism. The genes coding for dopamine receptors, serotonin transporters, and dehydrogenases represent susceptibility loci for addictive behaviour. However, alcoholism represents a complex psychiatric symptomatology which is caused by multiple factors, both genetic and environmental. Furthermore, there are probably different subtypes of alcoholism each with a distinct pathophysiology, and thus a different genetic background. Genetic research can help to identify such subtypes, which may require different therapeutic approaches. However, gene polymorphisms are not only responsible for a predisposition to alcoholism, but also for personality traits which influence the likelihood of developing addictive behaviour. Moreover, genetic polymorphisms are probably involved in the way an individual responds to treatment. Also, the severity of secondary diseases resulting from chronic alcohol uptake may depend on the genetic makeup of an individual. New treatment strategies focusing on genes contributing towards drug and alcohol dependence (such as gene therapy) are already under examination in animal models. However, further research is required before these developments will considerably change today's clinical handling of alcoholism.


Assuntos
Alcoolismo/genética , Polimorfismo Genético/genética , Alcoolismo/diagnóstico , Alcoolismo/terapia , Monoaminas Biogênicas/metabolismo , Humanos , Prognóstico
15.
Brain Res Mol Brain Res ; 14(1-2): 94-100, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1353857

RESUMO

The learned helpless rat is considered to be one of the better animal models of depression. A genetically inbred strain with a high vulnerability to develop helplessness (LH), as well as a highly resistant strain (NLH) have both been developed. Since the brain peptide neuropeptide Y (NPY) is involved in the regulation of a number of behaviors known to be altered in clinical depression as well as in learned helplessness, we measured the relative level of NPY mRNA in the hippocampus and cortex of control Sprague Dawley (SD), LH and NLH rats. We find that NLH rats have approximately a 30-35% decrease in basal hippocampal NPY mRNA compared with SD and LH rats. By contrast, cortical NPY mRNA and hippocampal pre-proenkephalin and somatostatin mRNA levels were not significantly different in the 3 strains. The data suggest that the regulation of NPY gene expression may be involved in the reduced vulnerability of NLH rats to develop learned helplessness.


Assuntos
Desamparo Aprendido , Hipocampo/metabolismo , Neuropeptídeo Y/biossíntese , Ratos Endogâmicos/genética , Isomerases de Aminoácido/biossíntese , Animais , Aprendizagem por Associação , Proteínas de Transporte/biossíntese , Córtex Cerebral/metabolismo , Suscetibilidade a Doenças/metabolismo , Encefalinas/biossíntese , Reação de Fuga , Expressão Gênica , Predisposição Genética para Doença , Malato Desidrogenase/biossíntese , Masculino , Neuropeptídeo Y/genética , Neuropeptídeo Y/fisiologia , Peptidilprolil Isomerase , Precursores de Proteínas/biossíntese , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos/psicologia , Somatostatina/biossíntese
16.
Schizophr Res ; 41(3): 389-95, 2000 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-10728716

RESUMO

The authors performed a MRSI study of the anterior cingulate gyrus in 19 schizophrenic patients under stable medication and 16 controls in order to corroborate previous findings of reduced NAA in the anterior cingulate region in schizophrenia. Furthermore, correlations between NAA in the anterior cingulate gyrus and age or illness duration have been determined. A decreased NAA signal was found in the anterior cingulate gyrus of patients compared to controls. Subdividing the patient group into two groups depending on medication revealed that the group of patients receiving a typical neuroleptic medication showed a lower mean NAA in comparison to the group of patients receiving atypical antipsychotic drugs. No significant group differences in the creatine and phosphocreatine signal or the signal from choline-containing compounds were found. The NAA signal significantly correlated with age, and therefore, individual NAA values were corrected for the age effect found in the control group. The age-corrected NAA signal in schizophrenia correlated significantly with the duration of illness. The detected correlations of NAA decrease with age and illness duration are consistent with recent imaging studies where progressing cortical atrophy in schizophrenia was found. Further studies will be needed to corroborate a possible favorable effect of atypical antipsychotics on the NAA signal.


Assuntos
Antipsicóticos/administração & dosagem , Ácido Aspártico/análogos & derivados , Giro do Cíngulo/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Esquizofrenia/tratamento farmacológico , Adulto , Antipsicóticos/efeitos adversos , Ácido Aspártico/metabolismo , Doença Crônica , Clozapina/efeitos adversos , Clozapina/uso terapêutico , Creatina/metabolismo , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fosfocreatina/metabolismo , Valores de Referência , Risperidona/efeitos adversos , Risperidona/uso terapêutico , Esquizofrenia/fisiopatologia , Resultado do Tratamento
17.
Schizophr Res ; 39(1): 19-29, 1999 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-10480664

RESUMO

Brain function and laterality in schizophrenia were investigated by means of a simple motor task with a self-generated left-hand sequential finger opposition (SFO) using a whole-brain high-speed (100 ms per slice) functional imaging technique. Neuroleptic-naïve, acutely ill schizophrenic patients were compared to schizophrenic patients under stable neuroleptic medication and matched controls. The goal was to evaluate both the motor function in first-episode patients and possible effects of different neuroleptic treatments on functional MRI results. Forty patients satisfying ICD 10 criteria (F20.x) for schizophrenia and sex- and age-matched healthy volunteers participated in this study. All subjects underwent fMRI examinations on a conventional 1.5 T MR unit. The primary sensorimotor cortex and the high-order supplementary motor area (SMA) were evaluated. There was a close similarity in the activation of the primary and high-order (SMA) sensorimotor areas between first-episode schizophrenic patients and controls. In contrast, a significant reduction in the overall blood oxygen level dependent (BOLD) response was seen in sensorimotor cortices (contra- and ipsilateral) in schizophrenic patients under stable medication with typical neuroleptics. This effect was not present in patients treated with atypical antipsychotics. Both antipsychotic treatments, however, led to a significant reduction in activation of the SMA region compared to controls and neuroleptic-naïve subjects. Thus, the present study provides no evidence for the localized involvement of the primary motor cortex or the SMA as a relatively stable vulnerability marker in schizophrenia. There is, however, strong evidence that neuroleptics themselves influence fMRI activation patterns and that there are major differences between typical neuroleptics and atypical antipsychotics.


Assuntos
Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Córtex Motor/anatomia & histologia , Córtex Motor/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Risperidona/efeitos adversos , Esquizofrenia/tratamento farmacológico , Córtex Somatossensorial/anatomia & histologia , Córtex Somatossensorial/efeitos dos fármacos , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Motor/fisiopatologia , Oxigênio/sangue , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Córtex Somatossensorial/fisiopatologia
18.
Neurochem Int ; 21(1): 29-35, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1303140

RESUMO

Sprague-Dawley rats exposed to uncontrollable shock can be separated by a subsequent shock escape test into two groups: a "helpless" (LH) group which demonstrates a deficit in escape behavior, and a "nonlearned helpless" (NLH) group which shows no escape deficit and acquires the escape response as readily as naive control rats (NC) do. The present studies were designed to examine the correlations between the behavioral differences and the changes of in vitro neurotransmitter release seen in these three groups of rats. The major finding concerned a significant increase in endogenous and K(+)-stimulated serotonin (5-HT) release in the hippocampal slices of LH rats. There were no apparent differences in acetylcholine, dopamine and noradrenaline release in the hippocampus of LH rats as compared to NLH and NC rats. These results add further support to previous studies in our laboratory which implicate presynaptic 5-HT mechanisms in the behavioral deficit caused by uncontrollable shock.


Assuntos
Depressão/fisiopatologia , Desamparo Aprendido , Hipocampo/metabolismo , Serotonina/metabolismo , Acetilcolina/metabolismo , Animais , Depressão/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Eletrochoque , Reação de Fuga , Hipocampo/efeitos dos fármacos , Técnicas In Vitro , Masculino , Norepinefrina/metabolismo , Potássio/farmacologia , Ratos , Ratos Sprague-Dawley
19.
Brain Res ; 615(2): 304-9, 1993 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-8364739

RESUMO

Learned helplessness (LH) is induced by exposure to an inescapable or uncontrollable stressor which results in an inability to escape or avoid the same stressor when subsequently presented in a different context. In order to understand which central mechanisms may influence the expression of the learned helpless phenotype, we have pursued an experimental approach that seeks to elucidate the behavioral effects of glucocorticoid (GC) hormones in this animal model of depression. We have previously shown that the induction of LH behavior is enhanced by adrenalectomy, an effect that is reversed by corticosterone. In this study, our aim was to attempt to locate CNS sites responsible for the observed effects of glucocorticoids on learned helpless behavior by introducing the type II GC receptor antagonist, RU 38486 to discrete brain regions. We did not observe a significant effect in LH with acute systemic, acute dentate gyrus or intracerebroventricular injection of RU 38486 in contrast to previous studies using the Porsolt swim test, another animal model of depression. However, we were able to observe a significant change upon chronic administration to the dentate gyrus. These findings suggest that glucocorticoids exert a long-term influence on stress-induced behavior, presumably by affecting glucocorticoid responsive genes in the dentate gyrus.


Assuntos
Glucocorticoides/antagonistas & inibidores , Desamparo Aprendido , Mifepristona/farmacologia , Animais , Hipocampo/fisiologia , Injeções , Injeções Intraventriculares , Injeções Subcutâneas , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
20.
Brain Res ; 271(1): 180-3, 1983 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-6883117

RESUMO

Adenosine uptake by cultured cerebral endothelium is a carrier-mediated process. The Km value for adenosine uptake is 5.0 microM and the vmax is 1.15 nmol/min/mg cell protein. The uptake system is inhibited by the adenosine analog 2-chloroadenosine at low adenosine concentrations. The results prove the existence of a nucleoside transport system associated with cerebral capillary endothelium.


Assuntos
Adenosina/metabolismo , Circulação Cerebrovascular , 2-Cloroadenosina , Adenosina/análogos & derivados , Adenosina/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Radioisótopos de Carbono , Linhagem Celular , Células Cultivadas , Circulação Cerebrovascular/efeitos dos fármacos , Dipiridamol/farmacologia , Endotélio/efeitos dos fármacos , Endotélio/metabolismo , Cinética , Camundongos , Papaverina/farmacologia , Sacarose/metabolismo , Trítio
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