Neurobiologia en estres y trauma

Neurobiología en Neurobiología en Estrés y TraumaEstrés y Trauma

Dr. Enrique De RosaDr. Enrique De [email protected] [email protected]

www.consultapsi.com www.consultapsi.com

www.estrestraumatico.com www.estrestraumatico.com

AAPI 2003AAPI 2003

Fuentes de estrés:Fuentes de estrés:• Gastos, la falta de dinero, la persistente recensión

económica, • Desocupación, • Desbordes sociales, Incremento del delito,

Inseguridad• Demandas y frustraciones de la escuela, • Cambios en sus cuerpos, • Problemas con sus amigos• el vivir en un ambiente/vecindario poco seguro, • Peleas frecuentes entre los padres • Separación o divorcio de sus padres, • Enfermedad crónica o problemas severos en la

familia, • Muerte de un ser querido- (Hoy suicidios, víctimas v.

urbana etc) • Mudarse o cambiar de escuela• Llevar a cabo demasiadas actividades o tener

expectativas demasiado altasRed PsyGnos.net - - ConsultaPsi.com

http://www.psygnos.net/


http://www.consultapsi.com/

Trauma.Trauma.

1.Lesión duradera producida por un agente mecánico, generalmente externo.

2. Choque emocional que produce un daño duradero en el inconsciente.

3. Emoción o impresión negativa, fuerte y duradera.

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Espectro de las Espectro de las reacciones al estrésreacciones al estrés

• Trastorno por estrés agudo• Psicosis reactiva breve• Trastornos disociativos

– fuga disociativa– amnesia disociativa– personalidad múltiple

• Trastornos conversivos• Trastornos adaptativos• Trastornos fóbicos• Trastornos depresivos

– depresión reactiva– depresión postraumática

• Trastorno de despersonalización

• Trastornos del sueño• Trastornos por somatización• Trastornos de personalidad

– borderline– antisocial– depresiva

• Cambio de personalidad– catastrófica– TEENE

• DESNOS (trastorno de estrés extremo no especificado)





Patología psiquiátrica Patología psiquiátrica postraumáticapostraumática• Trastornos de ansiedadTrastornos de ansiedad

• Síndrome de Stress postraumáticoSíndrome de Stress postraumático• Trastorno por estrTrastorno por estrés agudoés agudo

• Trastornos del estado de ánimoTrastornos del estado de ánimo• Síndromes depresivosSíndromes depresivos

• Trastornos adaptativosTrastornos adaptativos• Trastornos disociativosTrastornos disociativos• PsicosisPsicosis• Trastornos Psiquiátricos debidos a una condición Trastornos Psiquiátricos debidos a una condición médicamédica

• EpilepsiaEpilepsia• DemenciaDemencia• Síndrome Postconmocional de los traumatizados Síndrome Postconmocional de los traumatizados de cráneode cráneo

• Trastornos relacionados con abuso de sustanciasTrastornos relacionados con abuso de sustancias• Trastornos SomatoformesTrastornos Somatoformes

• DismorfofobiaDismorfofobia• Somatizaciones o enfermedades psicosomáticasSomatizaciones o enfermedades psicosomáticas• Síndromes ConversivosSíndromes Conversivos

PTSD: SPTSD: Síntomas nuclearesíntomas nucleares

Aumento de la respuesta autónomica (H)

Reexperiencia del hecho traumático (I)

Evitamiento (A)

Anestesia efectiva





1.SNV.

2.Eje Hipotálamo-Hipófisis-Suprarrenal

3.Locus Coeruleus.

4.Amígdala/hipocampo

5.Corteza prefrontal





visual

gustativa

kinestética

olfativaauditiva

TÁLAMOTÁLAMO

AmígdalaAmígdalaHIPOCAMPOHIPOCAMPO

Cognitive mapCognitive map

CortexCortex Pre-frontalPre-frontal





Prenatal stress produces learning Prenatal stress produces learning deficits associated with an inhibition deficits associated with an inhibition of neurogenesis in the hippocampus of neurogenesis in the hippocampus

Lemaire,Koehl, Le Moal & Abrous Bordeaux IIEarly experiences such as prenatal stress

significantly influence the development of the brain and the organization of behavior. In particular, prenatal stress impairs memory processes but the mechanism for this effect is not known. Hippocampal granule neurons are generated throughout life and are involved in hippocampal-dependent learning. Here, we report that prenatal stress in rats induced lifespan reduction of neurogenesis in the dentate gyrus and produced impairment in hippocampal-related spatial tasks. Prenatal stress blocked the increase of learning-induced neurogenesis. These data strengthen pathophysiological hypotheses that propose an early neurodevelopmental origin for psychopathological vulnerabilities in aging.

http://www.pnas.org/cgi/content/full/97/20/11032?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=1&fulltext=stress%2C+hip*&searchid=1061210973828_1959&stored_search=&FIRSTINDEX=0&sortspec=relevance#FN151

TEPTTEPT

Cuadros clínicos que se estructuran posteriormente a un trauma real o

imaginario único o repetido y de alta o baja intensidad.

Es diametralmente diferente a un cuadro por estrés

La sintomatología se estructura alrededor de 3 ejes:

alerta (arousal)evitamientorevivir el hecho traumático





TEPT en los niñosTEPT en los niñosDSM IVDSM IV

A - Si ha vivido o presenciado, acontecimientos de muerte o amenazas para su integridad física o de su entorno

(violencia familiar, abuso sexual).–Pueden manifestarse con trast. Del comportamiento o agitación psicomotriz






B– El trauma es reexperimentado

• En niños pequeños:– juegos y dibujos repetitivos donde aparecen

temas o aspectos del trauma– Sueños terroríficos (pesadillas)– Dramatización del acontecimiento traumático – Malestar psicológico intenso (Llantos, temores

obsesivos, fobias)– Quejas psicosomáticas






C– Evitación ante estímulos asociados al

trauma.• El niño no cuenta lo sucedido• Evita los lugares asociados al hecho traumático• Temor ante el abusador• Sensación de desapego• Aislamiento• Incapacidad para expresar afectos• Sensación de culpabilidad por lo sucedido






D– Síntomas persistentes de aumento de

activación ( arousal )• Dificultad para conciliar o mantener el

sueño• Irritabilidad y ataques de ira• Menor concentración• Hipervigilancia• Respuestas exageradas de sobresalto






E– Las alteraciones se prolongan por

más de 1 mes (Criterios B-C-D)





Cuadros clínicos de estrés post Cuadros clínicos de estrés post traumáticos más habituales en traumáticos más habituales en

niños para el DSM IVniños para el DSM IV• Estrés agudo

– Menos de 1 mes

• TEPT– Más de 1 mes

• Trastorno Disociativo





Tipos de traumaTipos de trauma

• Directo• Indirecto

– Presencial (violencia doméstica)– Ser testigo (accidente de tránsito)– Ser informado (relatos)– (virtual) imágenes por TV, PC– Transgeneracional– Vicario (“contagio del trauma”)– Varios: desgaste laboral en menores





Síntomas comunes en Síntomas comunes en los niñoslos niños

• Temores obsesivos• Alteraciones del sueño• Hipervigilancia• Tendencia al llanto• Falta de entusiasmo• Impulsividad• Agresividad excesiva• Conflicto con compañeros• Quejas psicosomáticas• Enfermedad o accidentes frecuentes





Abuso InfantilAbuso Infantil• Son fenómenos con altísima incidencia

socio-cultural• Es un concepto que continúa en

evolución según investigaciones médicas, sociológicas y psicológicas

• Incluye negligencia, daño emocional abusos físicos, explotación y abuso sexual.

• Es un área de abordaje escencialmente interdisciplinaria





Síntomas de abuso Infantil Síntomas de abuso Infantil según la edadsegún la edad

• Preescolar:– Ansiedad– Retraimiento– Culpabilidad– Quejas somáticas– Alteración del apetito– Ansiedad de separación– Alteraciones del sueño– Pesadillas– Hiperactividad– Mentiras– Falta de confianza– Fobias– Regresiones– Conocimiento sexual inapropiado para la edad– Agresividad– Ausencia de síntomas





• Edad escolar y adolescentes.– Ansiedad– Retraimiento– Culpabilidad– Quejas somáticasAlteración del apetito– Alteraciones del sueño– Enuresis encopresis– Pesadillas– Depresión – Fobias– Dificultades escolares– Crisis de angustia – Mala relación con los compañeros– Huida del hogar– Intentos de suicidio– Tics– Hostilidad y negativismo– Agresividad– Pasividad– Delincuencia– Conducta sexual– Obsesiones Psicosis– Ausencia de síntomas





SecuelasSecuelas• Mayor cantidad de síntomas psiquiátricos en

los adultos• Menor cociente intelectual a expensas del CI

verbal en los test estandarizados• Mayor incidencia de intentos de suicidio• En los estudios neurocognitivos• Alteraciones de la memoria, sensopercepción y

conducta• Alteraciones del eje hipotálamo-hipófiso

suprarrenal-amígdalo-hipocámpico-corteza frontal contralateral.





Tipos de Abuso InfantilTipos de Abuso Infantil• Negligencia• Abuso emocional• Abuso físico• Abuso sexual





NivelesNiveles

MemoriaMemoria

Áreas de importancia Diencéfalo:

- Núcleos :- dorsomedial- medial

- Hipocampo- Núcleo dentado- Hipocampo- Gyrus parahipocámpico

Núcleos AmígdalinosTalámico medialMediales lóbulo temporal

HipocampoHipocampo

AmigdalAmigdalaa

• Corpus Callosum (CC) • Lateral Ventricle (LV) • Fornix (F, both dorsally

and ventrally) • Body of Caudate (C) • Stria Terminalis (ST) • Stria Medullaris

Thalami (SMT) • Choroid Plexus forming

roof of (3V) • Mediodorsal N (MD) • Lateral Dorsal N (LD) • Internal Medullary

Lamina (IML) • Ventral Lateral N (VL) • External Medullary

Lamina (EML) • Reticular Nucleus (R)

and Zona Incerta (ZI)

• External Medullary Lamina (EML)

• Reticular Nucleus (R) and Zona Incerta (ZI)

• Subthalamic Nucleus (STN)

• Internal Capsule (IC) • Extreme Capsule (ExmC) • Claustrum (Cl) • External Capsule (ExlC) • Putamen (P) • Globus Pallidus (GP) • Optic Tract (OT) • Amygdala • Lenticular Fasciculus

(LF) • Thalamic Fasciculus (TF,

Mammillothalamic Tract (MTT)

• Tuber cinereum (TC,)

Estrés: cortisol hipocampo (pérdida neuronal-overpruning)

Trauma cortisol aguda crónica

• Sensibilidad a los receptores de glucocorticóides atrofia hipocámpica

• Depresión resistencia a los glucocort. No hay atrofia

Red PsyGnos.net Red PsyGnos.net - - ConsultaPsi.comConsultaPsi.com

Psicofisiológicos

+++ respuesta autónoma a est.traumáticos

++ resp.est. Neutros > intens. (pérdida discriminación).

• No habituación startle response

• Resp. debajo umbral en + sonoros (timbre, teléfono)

Neuroanatómicos

volumen hipocámpico

Activación áreas sensitivas y amigdala

Menor actividad de Broca

Mayor act. Hemisferio no dominante

Est., como respuesta física, emocional y no verbal

Janet 1889 - Emoción intensa disocia de la

conciencia y se guarda como

sensaciones . Cuando las emociones son

intensas, no pueden ser integradas en

una narrativa

•Fragmentarias-•L'Automatisme Psychologique.


La naturaleza disociartiva de la

memoria traumática es lo

que la distingue de la experoencia

cotidiana

La D. En el momento del

trauma se transformó en el

predictor más importante de

desarrollo de PTSD

Freud fijación tuviera base

biológicaIntroduction to Psychoanalysis

and the War Neuroses

Pavlov CR. Los eventos

ocurren una y otra vez

( recuerdos)Red PsyGnos.net Red PsyGnos.net - - ConsultaPsi.comConsultaPsi.com

PsyGnos – Centro de Estudios y Terapias CognitivasPsyGnos – Centro de Estudios y Terapias Cognitivas

visual

gustativa

kinestética

olfativaauditiva

TÁLAMOTÁLAMO

AmígdalaAmígdalaHIPOCAMPOHIPOCAMPO

Cognitive mapCognitive map

CortexCortex Pre-frontalPre-frontal

•Más temprano el trauma, mayor elemento disociativo, más amnesia, más temprano

•Alteración en el proceso de plasticidad neuronal Attachment


Estrés-Trauma-PTSD: Estrés-Trauma-PTSD: Espectro clínicoEspectro clínico

Conjunto de Elementos y Conjunto de Elementos y respuestasrespuestas

•CognitivasCognitivas•ComportamentalesComportamentales

•EmocionalesEmocionales•FisiológicosFisiológicos•AnatómicosAnatómicos

----------------------------------------------•SocialesSociales



Organización de la Organización de la experiencia auditiva experiencia auditiva

MiedoMiedo

Hipocampo

Amigdala

Tálamo auditivo

Corteza Auditiva



Trauma.Trauma.

• 1. m. Lesión duradera 1. m. Lesión duradera producida por un agente producida por un agente mecánico, generalmente mecánico, generalmente externo. externo.

• 2. m. Choque emocional que 2. m. Choque emocional que produce un daño duradero en produce un daño duradero en el inconsciente. el inconsciente.

• 3. m. Emoción o impresión 3. m. Emoción o impresión negativa, fuerte y duradera.negativa, fuerte y duradera.


VulnerabilidadCalidad

de Vida

Soportes

Afectivos

Sucesos Vitales

GatilladorGatillador

Enfermedad

Zukerfeld R y Zukerfeld Z. Psicoanálisis Tercera tópica y vulnerabilidad somática. Lugar 1999: 47.

Stress-induced changes in cerebral Stress-induced changes in cerebral metabolites, hippocampal volume, and metabolites, hippocampal volume, and

cell proliferation prevented by cell proliferation prevented by tianeptinetianeptine

Boldizsár Czéh, October 2, 2001, 10.1073 Boldizsár Czéh, October 2, 2001, 10.1073 /pnas.211427898/pnas.211427898

Stress-induced structural remodeling in the adult hippocampus, Stress-induced structural remodeling in the adult hippocampus, involving debranching and shortening of dendrites and suppression involving debranching and shortening of dendrites and suppression of neurogenesis, provides a cellular basis for understanding the of neurogenesis, provides a cellular basis for understanding the impairment of neural plasticity in the human hippocampus in impairment of neural plasticity in the human hippocampus in depressive illness. Accordingly, reversal of structural remodeling depressive illness. Accordingly, reversal of structural remodeling may be a desirable goal for antidepressant therapy. Animals were may be a desirable goal for antidepressant therapy. Animals were subjected to a 7-day period of psychosocial stress to elicit stress-subjected to a 7-day period of psychosocial stress to elicit stress-induced endocrine and central nervous alterations before the onset induced endocrine and central nervous alterations before the onset of daily oral administration of tianeptine (50 mg/kg). of daily oral administration of tianeptine (50 mg/kg).

Chronic psychosocial stress significantly decreased Chronic psychosocial stress significantly decreased in vivoin vivo concentrations of concentrations of NN-acetyl-aspartate ( 13%), creatine and -acetyl-aspartate ( 13%), creatine and phosphocreatine ( 15%), and choline-containing compounds ( 13%). phosphocreatine ( 15%), and choline-containing compounds ( 13%). The proliferation rate of the granule precursor cells in the dentate The proliferation rate of the granule precursor cells in the dentate gyrus was reduced ( 33%). These stress effects were prevented by gyrus was reduced ( 33%). These stress effects were prevented by the simultaneous administration of tianeptine. the simultaneous administration of tianeptine.

In stressed animals treated with tianeptine, hippocampal volume In stressed animals treated with tianeptine, hippocampal volume increased above the small decrease produced by stress alone. increased above the small decrease produced by stress alone. These findings provide a cellular and neurochemical basis for These findings provide a cellular and neurochemical basis for evaluating antidepressant treatments with regard to possible evaluating antidepressant treatments with regard to possible reversal of structural changes in brain that have been reported in reversal of structural changes in brain that have been reported in depressive disorders. depressive disorders.

Prenatal stress produces learning Prenatal stress produces learning deficits associated with an deficits associated with an

inhibition of neurogenesis in the inhibition of neurogenesis in the hippocampus hippocampus

Lemaire,Koehl, Le Moal & AbrousLemaire,Koehl, Le Moal & Abrous Bordeaux IIBordeaux IIEarly experiences such as prenatal Early experiences such as prenatal stressstress significantly significantly

influence the development of the brain and the organization of influence the development of the brain and the organization of behavior. In particular, prenatal behavior. In particular, prenatal stressstress impairs memory impairs memory processes but the mechanism for this effect is not known. processes but the mechanism for this effect is not known. HippocampalHippocampal granule neurons are generated throughout life granule neurons are generated throughout life and are involved in and are involved in hippocampalhippocampal-dependent learning-dependent learning. Here, . Here, we report that prenatal we report that prenatal stressstress in rats induced lifespan in rats induced lifespan reduction of neurogenesis in the dentate gyrus and produced reduction of neurogenesis in the dentate gyrus and produced impairment in impairment in hippocampalhippocampal-related spatial tasks. Prenatal -related spatial tasks. Prenatal stressstress blocked the increase of learning-induced neurogenesis. blocked the increase of learning-induced neurogenesis. These data strengthen pathophysiological hypotheses that These data strengthen pathophysiological hypotheses that propose an early neurodevelopmental origin for propose an early neurodevelopmental origin for psychopathological vulnerabilities in aging. psychopathological vulnerabilities in aging.


Experimental diabetes in rats Experimental diabetes in rats causes hippocampal dendritic and causes hippocampal dendritic and

synaptic reorganization and synaptic reorganization and increased glucocorticoid reactivity increased glucocorticoid reactivity

to stressto stressMagariños and McEwen Magariños and McEwen The Rockefeller UniversityThe Rockefeller UniversityChronic stressor that produces retraction and simplification of Chronic stressor that produces retraction and simplification of

apical dendrites of hippocampal pyramidal neurons. Diabetes apical dendrites of hippocampal pyramidal neurons. Diabetes also induces morphological changes in the presynaptic mossy also induces morphological changes in the presynaptic mossy fiber terminals that form excitatory synaptic contacts with the fiber terminals that form excitatory synaptic contacts with the proximal apical dendrites. One effect, synaptic vesicle depletion, proximal apical dendrites. One effect, synaptic vesicle depletion, occurs in diabetes as well as after repeated stress and Cort occurs in diabetes as well as after repeated stress and Cort treatment. However, diabetes produced other MFT structural treatment. However, diabetes produced other MFT structural changes that differ qualitatively and quantitatively from other changes that differ qualitatively and quantitatively from other treatments. Furthermore, whereas 7 d of repeated stress was treatments. Furthermore, whereas 7 d of repeated stress was insufficient to produce dendritic or synaptic remodeling in insufficient to produce dendritic or synaptic remodeling in nondiabetic rats, it potentiated both dendritic atrophy and MFT nondiabetic rats, it potentiated both dendritic atrophy and MFT synaptic vesicle depletion in STZ rats. These changes occurred in synaptic vesicle depletion in STZ rats. These changes occurred in concert with adrenal hypertrophy and elevated basal Cort release concert with adrenal hypertrophy and elevated basal Cort release as well as hypersensitivity and defective shutoff of Cort secretion as well as hypersensitivity and defective shutoff of Cort secretion after stress. Thus, as an endogenous stressor, STZ diabetes not after stress. Thus, as an endogenous stressor, STZ diabetes not only accelerates the effects of exogenous stress to alter only accelerates the effects of exogenous stress to alter hippocampal morphology; it also produces structural changes that hippocampal morphology; it also produces structural changes that overlap only partially with those produced by stress and Cort in overlap only partially with those produced by stress and Cort in the nondiabetic state.the nondiabetic state.

Adptación-EjeAdptación-EjeLimbic-hypothalamic-pituitary-adrenal axis in Limbic-hypothalamic-pituitary-adrenal axis in

depression: literature review depression: literature review Twardowska K; Rybakowski JTwardowska K; Rybakowski JKliniki Psychiatrii Dorosych w Poznaniu. Kliniki Psychiatrii Dorosych w Poznaniu. Psychiatr Psychiatr PolPol, 1996 Sep, 30:5, 741-55, 1996 Sep, 30:5, 741-55

Increased cortisol concentration has until now been the best Increased cortisol concentration has until now been the best documented biochemical abnormality in depression. documented biochemical abnormality in depression. Pathological results of the Dexamethasone Suppression Pathological results of the Dexamethasone Suppression Test pointing to hyperactivity of LHPA axis are found in Test pointing to hyperactivity of LHPA axis are found in about half of depressive patients. According to most recent about half of depressive patients. According to most recent research, primary disturbance of LHPA axis concerns research, primary disturbance of LHPA axis concerns hypothalamus and limbic system. An association was found hypothalamus and limbic system. An association was found between disturbances of LHPA axis in depression and between disturbances of LHPA axis in depression and immune system abnormalities in this illness. Disturbances immune system abnormalities in this illness. Disturbances of serotonergic and noradrenergic neurotransmission in of serotonergic and noradrenergic neurotransmission in depression may also partially result from LHPA axis depression may also partially result from LHPA axis dysfunction. Influencing LHPA axis may underlie the dysfunction. Influencing LHPA axis may underlie the mechanism of new antidepressant drug, tianeptine. mechanism of new antidepressant drug, tianeptine. Recently, it was found that classical tricyclic antidepressant Recently, it was found that classical tricyclic antidepressant drugs as well as electroconvulsive may also act on LHPA in drugs as well as electroconvulsive may also act on LHPA in regulatory way.regulatory way.

Adptación-EjeAdptación-Eje

Watanabe Y, Gould E, Daniels DC, Cameron H, McEwen BS.Laboratory of Neuroendocrinology, Rockefeller University, New York, NY 10021.

Repeated 6-h daily restraint stress over 21 days reduces length and number of branch points of hippocampal CA3c pyramidal dendrites in the hippocampal formation of adult male rats. This effect is mimicked by daily injections of 40 mg/kg corticosterone. Daily treatment with tianeptine (15 mg/kg) prior to stress sessions or the corticosterone treatment prevented these effects of stress or corticosterone, respectively. Tianeptine treatment did not prevent the effects of stress to increase adrenal/body weight ratio, nor did it prevent the effects of stress to decrease body weight gain, indicating that its actions are not mediated solely by effects on stress-induced secretion of corticosterone. Because tianeptine is known to enhance neural uptake of serotonin, these results suggest that the serotonergic system may be involved in modulating stress and corticosterone effects on dendritic morphology.

Adptación-EjeAdptación-EjeDelbende C, Contesse V, Mocaer E, Kamoun A, Vaudry H.

European Institute for Peptide Research, CNRS URA 650.

The possible effect of tianeptine, a novel antidepressant agent, on the neuroendocrine response to stress was investigated in adult male rats. Tube restraint stress for 30 min induced a marked increase of plasma ACTH and corticosterone. A single i.p. injection of tianeptine (10 mg/kg), 120 min before stress caused a significant decrease of ACTH and corticosterone levels. In order to investigate the kinetics of the effect of tianeptine, the drug was injected at various times (from 15 min to 12 h) before restraint stress. The inhibitory effect of tianeptine on stress-induced elevations of plasma ACTH and corticosterone occurred from 1 to 3 h after the injection. Administration of increasing doses of tianeptine revealed that only the highest doses (10 and 20 mg/kg) had a significant effect on stress-evoked stimulation of ACTH and corticosterone secretion. These results show that the antidepressant, tianeptine, reduces the activation of the hypothalamo-pituitary-adrenal (HPA) axis induced by restraint stress. Since depressed patients generally exhibit an elevated cortisol level, the present data suggest that part of the therapeutic properties of tianeptine could be accounted for by the effect of this antidepressant to modulate the activity of the HPA axis.

Stress facilitates classical Stress facilitates classical conditioning in males, but impairs conditioning in males, but impairs classical conditioning in females classical conditioning in females

through ovarian hormones through ovarian hormones Gwendolyn E. Wood and Tracey J. Shors Princeton UniversityExposure to restraint and brief intermittent tailshocks facilitates

associative learning of the classical conditioned eyeblink response in male rats. Based on evidence of sex differences in learning and responses to stressful events, we investigated sexually dimorphic effects of a stressor of restraint and intermittent tailshock on classical eyeblink conditioning 24 h after stressor cessation. Our results indicate that exposure to the acute stressor had diametrically opposed effects on the rate of acquisition of the conditioned response in male vs. female rats. Exposure to the stressor facilitated acquisition of the conditioned response in males, whereas exposure to the same stressful event dramatically impaired acquisition in females. We further demonstrate that the stress-induced impairment in female conditioning is dependent on the presence of ovarian hormones. Conditioning of stressed sham-ovariectomized females was significantly impaired relative to the unstressed controls, whereas conditioning in stressed ovariectomized females was not impaired. We present additional evidence that estrogen mediates the stress-induced impairment in female acquisition. Females administered sesame oil vehicle and then stressed were significantly impaired relative to their unstressed controls, whereas females administered the estrogen antagonist tamoxifen prior to stress were not impaired. In summary, these results indicate that exposure to the same aversive event can induce opposite behavioral responses in males vs. females. These effects underscore sex differences in associative learning and emotional responding, and implicate estrogen in the underlying neuronal mechanism

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• Despland JN, Monod L, Ferrero F: Clinical relevance of adjustment disorder in DSM-III-4 and DSM-IV. Compr Psychiatry 1995 Nov-Dec; 36(6): 454-60.

• Greenberg WM, Rosenfeld DN, Ortega EA: Adjustment disorder as an admission diagnosis. Am J Psychiatry 1995 Mar; 152(3): 459-61

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• Polyakova I, Knobler HY, Ambrumova A, Lerner V: Characteristics of suicidal attempts in major depression versus adjustment reactions. J Affect Disord 1998 Jan; 47(1-3): 159-67[Medline].

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Neurobiologia en estres y trauma