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1.
Nervenarzt ; 82(8): 1012-9, 2011 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-21523443

RESUMEN

BACKGROUND: Parkinson's disease (PD) is frequently accompanied by dementia or depression which can aggravate the clinical picture of the disease and increase the risk of care dependency (CD). Little is known about the associations between PD, these neuropsychiatric comorbidities and CD in outpatients. PATIENTS AND METHODS: A nationwide sample of outpatients (n=1,449) was examined by office-based neurologists (n=315) comprising the documentation of the general, neurological status and the degree of CD. The dementia status was clinically rated according to the established DSM-IV criteria. Depression was screened with the Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: Overall, 18.3% of all patients were care dependent. Even after adjustment for PD severity, patients with depression (OR=2.8; 95% CI 1.8-4.3), dementia (OR=2.7; 95% CI 1.8-4.1) or both (OR=3.9; 95% CI 2.5-60,0) were at higher risk for CD than patients without dementia or depression. Patients aged ≥76 years were fourfold more likely to be care dependent than patients aged ≤65 years (OR=3.5; 95% CI 2.3-5.5). Across all age groups, patients with depression featured the highest increments (from 11.9 to 42.0%). CONCLUSION: The risk for CD is substantially elevated in outpatients with PD when further neuropsychiatric symptoms are present. The data suggest that depression contributes equally to disability as does dementia.


Asunto(s)
Demencia/epidemiología , Demencia/enfermería , Trastorno Depresivo/epidemiología , Trastorno Depresivo/enfermería , Evaluación de la Discapacidad , Evaluación en Enfermería , Enfermedad de Parkinson/epidemiología , Enfermedad de Parkinson/enfermería , Anciano , Anciano de 80 o más Años , Atención Ambulatoria/estadística & datos numéricos , Comorbilidad , Estudios Transversales , Demencia/diagnóstico , Trastorno Depresivo/diagnóstico , Femenino , Alemania , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico , Pruebas Neuropsicológicas , Enfermedad de Parkinson/diagnóstico
2.
MMW Fortschr Med ; 152 Suppl 1: 1-6, 2010 Apr 08.
Artículo en Alemán | MEDLINE | ID: mdl-20942300

RESUMEN

UNLABELLED: It is unknown, how frequently Parkinson's disease (PD) is complicated by dementia, depression and other neuropsychiatric conditions. An epidemiologic characterisation of the situation in specialised neurologic settings is lacking. The Geman Study on the Epidemiology of Parkinson's Disease with Dementia (GEPAD) isa national representative epidemiological study of n=1449 PD patients in n=315 office-based neurological settings, designed to estimate the prevalence of dementia, depression and other neuropsychiatric conditions in patients with PD of all stages by using standardized clinical assessments. RESULTS: 28.6% met DSM-IV criteria for dementia. 33.6% met criteria for depression and 61% additionally had other clinically significant psychopathological syndromes. Only 29.4% had no neuropsychiatric conditions. GEPAD reveals for the first time comprehensively that the neuropsychiatric burden of PD patients in all stages and even early stages is considerable, posing challenging questions for research and clinical management.


Asunto(s)
Trastornos del Conocimiento/epidemiología , Enfermedad por Cuerpos de Lewy/epidemiología , Enfermedad de Parkinson/epidemiología , Anciano , Trastornos del Conocimiento/clasificación , Trastornos del Conocimiento/diagnóstico , Comorbilidad , Estudios Transversales , Trastorno Depresivo/clasificación , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/epidemiología , Femenino , Alemania , Humanos , Enfermedad por Cuerpos de Lewy/clasificación , Enfermedad por Cuerpos de Lewy/diagnóstico , Masculino , Tamizaje Masivo , Escala del Estado Mental , Persona de Mediana Edad , Examen Neurológico , Pruebas Neuropsicológicas , Enfermedad de Parkinson/clasificación , Enfermedad de Parkinson/diagnóstico
3.
J Cell Biol ; 53(3): 654-61, 1972 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4402165

RESUMEN

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


Asunto(s)
Membrana Celular , Neuronas/citología , Adenosina Trifosfatasas/análisis , Animales , Fraccionamiento Celular , Membrana Celular/enzimología , Nucléolo Celular , Núcleo Celular , Centrifugación por Gradiente de Densidad , Corteza Cerebral/citología , Corteza Cerebral/enzimología , Citocromos , Complejo IV de Transporte de Electrones/análisis , Glucofosfatos/análisis , Métodos , Microscopía Electrónica , Microsomas/enzimología , Mitocondrias/enzimología , Monoaminooxidasa/análisis , NADP , Neuronas/enzimología , Oxidorreductasas/análisis , Conejos , Sacarosa
4.
Neurochem Res ; 34(9): 1584-93, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19288275

RESUMEN

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.


Asunto(s)
Depresión/metabolismo , Proteínas Transportadoras de GABA en la Membrana Plasmática/biosíntesis , Desamparo Adquirido , Ácido gamma-Aminobutírico/fisiología , Animales , Depresión/genética , Regulación hacia Abajo , Masculino , Ratas , Ratas Sprague-Dawley
5.
J Colloid Interface Sci ; 308(1): 216-21, 2007 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-17229436

RESUMEN

Thermally stimulated depolarization current (TSDC) technique is a powerful tool for probing dipole re-orientational motions in condensed matter. In the case of cation-exchangeable aluminosilicates, it allows the assessment of the potential barrier related to the hopping mechanism of cations and, consequently, the measurement of its evolution when molecules, i.e. water, are adsorbed and interact with the cations embedded in the solid framework. Then, using suitable models based on thermodynamics, the analysis of TSDC signals obtained at various hydration states provides insights about the surface properties of the studied solid and the mechanism of adsorption at the cationic site. In this work, TSDC is used to study the first stage, i.e. when the number of adsorbed molecules is below the occurrence of the water monolayer, of water adsorption in a Na(+)-montmorillonite from Mostaganem (Algeria). It is shown that the hydration process follows two stages. Using the "chemical force" concept it can then be concluded that when the number of adsorbed water molecules per cation is lower than 2, cation-water interaction dominates the energetics of adsorption, whereas at higher water loading the water "chemical force" is also involved into water-water and/or water-clay framework interactions. The number of water molecules for the monohydrated state is found to be about 7.

6.
J Colloid Interface Sci ; 306(2): 440-8, 2007 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-17126849

RESUMEN

This paper tries to assess simply and quantitatively the link between classical adsorption theories and dielectric spectroscopy, in order to demonstrate that dielectric spectroscopy can be used as a tool of determination of surface energy variations due to movements of charge carriers at the surface of solids. A simple theory is developed to analyze hops of cations at the surface of mordenite, which are detected by complex impedance spectroscopy during adsorption of water. An energy of extraction of the cation can be determined from measurements and its dependence on the quantity of water molecules adsorbed is shown and qualitatively and quantitatively explained, using relationships developed in order to interpret adsorption phenomena generally. The agreement with other determinations of the adsorption energies and solid surface energy is correct.

7.
J Phys Chem B ; 110(37): 18447-54, 2006 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-16970470

RESUMEN

Molecular dynamics simulations have been carried out to address the question of cation migration upon adsorption of methanol in NaY and NaX faujasite systems as a function of the loading. For NaY, it has been shown that, at low and intermediate loadings, SII cations can migrate toward the center of the supercage due to strong interactions with the adsorbates, followed by a hopping of SI' from the sodalite cage into the supercage to fill the vacant SII site. A SI' cation can also migrate across the double six ring and takes a SI' vacant position. SI cations mainly remain trapped in their initial sites whatever the loading. At high loading, only limited motions are observed for SII cations due to steric effects induced by the presence of adsorbates within the supercage. For NaX, the SIII' cations which occupy the most accessible adsorption sites are significantly moving upon coordination to the methanol molecules; the extent of this mobility exhibits a maximum for 48 methanol molecules per unit cell before decreasing at higher loadings due to steric hindrance. In addition, the SI' and SII cations remain almost trapped in their initial sites whatever the loading. Indeed, the most probable migration mechanism involves SIII' cation displacements into nearby SIII' sites.

8.
Arch Gen Psychiatry ; 37(10): 1160-3, 1980 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7425800

RESUMEN

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.


Asunto(s)
Crimen , Delincuencia Juvenil/psicología , Socialización , Adolescente , Agresión , Trastorno de Personalidad Antisocial/psicología , Trastornos de la Conducta Infantil/diagnóstico , Psicología Criminal , Humanos , Masculino , Pronóstico , Estudios Retrospectivos , Trastorno de la Conducta Social/psicología
9.
Arch Gen Psychiatry ; 57(10): 937-43, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11015811

RESUMEN

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.


Asunto(s)
Ácido Aspártico/análogos & derivados , Terapia Electroconvulsiva , Hipocampo/anatomía & histología , Hipocampo/metabolismo , Espectroscopía de Resonancia Magnética , Adulto , Ácido Aspártico/química , Ácido Aspártico/metabolismo , Muerte Celular , Colina/análisis , Colina/metabolismo , Creatina/análisis , Creatina/metabolismo , Femenino , Hipocampo/química , Humanos , Espectroscopía de Resonancia Magnética/estadística & datos numéricos , Masculino , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/etiología , Trastornos de la Memoria/metabolismo , Persona de Mediana Edad , Fosfatidilcolinas/análisis , Fosfatidilcolinas/metabolismo , Fosfocreatina/análisis , Fosfocreatina/metabolismo
10.
Biol Psychiatry ; 45(6): 737-42, 1999 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10188003

RESUMEN

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.


Asunto(s)
Envejecimiento/metabolismo , Enfermedad de Alzheimer/metabolismo , Calcio/metabolismo , Linfocitos T/metabolismo , Adulto , Anciano , Muerte Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitógenos/farmacocinética , Neuronas/metabolismo , Fitohemaglutininas/farmacocinética
11.
Biol Psychiatry ; 29(2): 159-75, 1991 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-1995085

RESUMEN

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.


Asunto(s)
Encéfalo/anatomía & histología , Imagen por Resonancia Magnética , Esquizofrenia/diagnóstico , Adolescente , Adulto , Factores de Edad , Ventrículos Cerebrales/anatomía & histología , Niño , Enfermedad Crónica , Femenino , Lateralidad Funcional , Humanos , Masculino , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/diagnóstico
12.
Biol Psychiatry ; 50(10): 809-12, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11720700

RESUMEN

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.


Asunto(s)
Proteínas de Unión al Calcio , Hipocampo/patología , Glicoproteínas de Membrana/genética , Proteínas del Tejido Nervioso/genética , Estrés Psicológico/complicaciones , Sinaptofisina/genética , Animales , Regulación de la Expresión Génica/fisiología , Plasticidad Neuronal/genética , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Restricción Física , Estrés Psicológico/patología , Sinaptotagminas
13.
Am J Psychiatry ; 139(12): 1601-3, 1982 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7149061

RESUMEN

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."


Asunto(s)
Trastorno Obsesivo Compulsivo/cirugía , Psicocirugía/métodos , Adulto , Femenino , Estudios de Seguimiento , Giro del Cíngulo/cirugía , Humanos , Trastorno Obsesivo Compulsivo/psicología
14.
Am J Psychiatry ; 134(5): 556-8, 1977 May.
Artículo en Inglés | MEDLINE | ID: mdl-557905

RESUMEN

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.


Asunto(s)
Psicología Criminal , Psiquiatría Forense , Trastornos Mentales/epidemiología , Síntomas Afectivos/epidemiología , Piromanía , Homicidio , Humanos , Histeria/epidemiología , Missouri , Trastornos Neuróticos/epidemiología , Esquizofrenia/epidemiología , Factores Sexuales , Control Social Formal , Violencia
15.
Am J Psychiatry ; 133(6): 694-6, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1275101

RESUMEN

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.


Asunto(s)
Psiquiatría Forense , Trastornos Mentales/diagnóstico , Delitos Sexuales , Alcoholismo/diagnóstico , Humanos , Trastornos Parafílicos/complicaciones , Pedofilia/complicaciones , Pedofilia/diagnóstico , Violación , Trastornos Relacionados con Sustancias/diagnóstico
16.
Am J Psychiatry ; 158(8): 1314-6, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11481168

RESUMEN

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.


Asunto(s)
Ácido Aspártico/análisis , Esquizofrenia/diagnóstico , Tálamo/química , Adulto , Ácido Aspártico/análogos & derivados , Colina/análisis , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Espectroscopía de Resonancia Magnética/estadística & datos numéricos , Masculino , Fosfocreatina/análisis , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología , Tálamo/fisiopatología
17.
Am J Psychiatry ; 149(5): 686-8, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1575261

RESUMEN

Because of the frequent association of cerebellar structural defects with schizophrenia, the authors reanalyzed the metabolic brain images of patients with chronic schizophrenia to assess if they had abnormalities in cerebellar metabolism. They used carbon-11-2-deoxyglucose and positron emission tomography to study 18 medicated patients with chronic schizophrenia and 12 normal comparison subjects. Patients with schizophrenia showed significantly lower absolute and relative metabolism in the cerebellum than normal subjects.


Asunto(s)
Cerebelo/metabolismo , Glucosa/metabolismo , Esquizofrenia/diagnóstico , Adulto , Radioisótopos de Carbono , Cerebelo/diagnóstico por imagen , Desoxiglucosa , Humanos , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Esquizofrenia/metabolismo , Tomografía Computarizada de Emisión
18.
Neuropsychopharmacology ; 3(2): 109-14, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2317263

RESUMEN

In the learned helplessness model of depression, naive Sprague-Dawley rats are exposed to a 40-minute uncontrollable shock training and are subsequently tested in a shock escape paradigm. "Helpless rats" exhibit 11 to 15 failures in a 15-trial test while "nonhelpless" rats and naive controls score 0 to 5 failures in the same test. We report on the effect of bilateral adrenalectomy on the induction of learned helplessness. Most of the adrenalectomized rats (70%) became helpless whereas sham controls responded to the training and testing similarly to naive nonoperated rats (20% to 30% helpless). This increase in behavioral deficits after adrenalectomy was reversed by administration of corticosterone, the naturally occurring glucocorticoid in rat. We conclude that secretion from the adrenal cortex is necessary for the incorporation of a learned response after stress and that a dysregulation of the hypothalamic-pituitary-adrenal axis seems to be involved in helpless behavior.


Asunto(s)
Adrenalectomía , Desamparo Adquirido , Animales , Corticosterona/farmacología , Depresión , Modelos Animales de Enfermedad , Electrochoque , Reacción de Fuga/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas
19.
Neuropharmacology ; 30(1): 101-5, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2046876

RESUMEN

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.


Asunto(s)
Encéfalo/metabolismo , Depresión/fisiopatología , Desamparo Adquirido , Receptores de Serotonina/metabolismo , Animales , Corteza Cerebral/metabolismo , Depresión/metabolismo , Modelos Animales de Enfermedad , Electrochoque , Reacción de Fuga , Hipocampo/metabolismo , Hipotálamo/metabolismo , Cinética , Masculino , Ratas , Ratas Endogámicas , Valores de Referencia
20.
Neuropharmacology ; 31(4): 323-30, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1387924

RESUMEN

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.


Asunto(s)
Encéfalo/metabolismo , Electrochoque , Reacción de Fuga , Serotonina/metabolismo , Estrés Psicológico/fisiopatología , Sinapsis/fisiología , Análisis de Varianza , Animales , Transporte Biológico , Desamparo Adquirido , Hipocampo/metabolismo , Hipotálamo/metabolismo , Técnicas In Vitro , Masculino , Modelos Psicológicos , Paroxetina , Piperidinas/metabolismo , Potasio/farmacología , Ratas , Ratas Endogámicas , Receptores de Serotonina/metabolismo , Antagonistas de la Serotonina/metabolismo , Sinapsis/efectos de los fármacos
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