Vasopressin Prolongs Behavioral and Cardiac Responses to Mild Stress in Young But Not in Aged Rats

In young male Wistar rats sudden silence superimposed on low intensity background noise evokes a relative decrease in heart rate. This bradycardia is accompanied by immobility behavior. In the present study, involving young (3 month), late-adult (14 month), aged (20 month), and senescent (25 month) rats the magnitude of the stress-induced bradycardia shows an age-related reduction while the behavioral immobility response remained unchanged during the process of aging. Arginine-8-vasopressin (AVP, 6 µg/kg SC) administered 60 min prior to the experiment led to a prolonged behavioral and cardiac stress response in young and late-adult rats, but not in aged and senescent animals. The peripheral and central mechanisms possibly involved in the failure of systemically applied AVP to improve bradycardiac stress responses in aged rats are discussed.

Behavioral and Cardiac Responses to Mild Stress in Young and Aged Rats:Effects of Amphetamine and Vasopressin

Young (3-month-old) male Wistar rats showed a relative decrease in heart rate to a sudden silence superimposed on low intensity background noise. This bradycardia was accompanied by immobility behavior. In 26-month-old rats the magnitude of the heart rate response was reduced while immobility behavior remained in the same order of magnitude as in young controls, in the aged rats a shift in autonomic regulation of heart rate in the direction of increased sympathetic influence was indicated by the results obtained by blocking the autonomic input with atropine methyl-nitrate (0.5 mg/kg) or atenolol (1 mg/kg) given subcutaneously (SC) 30 min prior to testing. Pretest (30 min) administration of amphetamine (0.5 mg/kg SC) reinstated the bradycardiac response in aged rats to a level seen in young ones. Arginine-vasopressin (AVP, 10 µg/kg SC), administered 60 rain before the experiment, markedly facilitated the cardiac response in young animals but failed to restore cardiac responses in aged ones. The immobility behavior in the peptide-treated aged rats was also absent. The present findings suggest that a diminished central aminergic drive in aged rats is causing a reduction of the parasympathetic cardiac response to stress of sudden silence. The results also indicate an age-related vasopressinergic modulation of behavioral and cardiac responses to mild stress

Reduced preabsorptive insulin response in aged rats:differential effects of amphetamine and arginine-vasopressin

The experiments presented here have been designed to investigate whether the age-related attenuation of the vagal reactivity to emotional stressors and its modulation by amphetamine (Amph) or arginine-vasopressin (AVP) can be generalized for other physiological response patterns. We therefore studied the vagal control of the endocrine pancreas during food intake. Young (3 months old) and aged (27 months old) male Wistar rats were provided with permanent cardiac catheters allowing free movement and repeated, stress-free blood sampling. The vagally mediated preabsorptive insulin response (PIR) in relation to food intake as seen in young rats was reduced in aged ones. Blood glucose increments were the same at both ages. Administration of Amph (0.5 mg/kg; s.c.) 30 min before, or AVP (10 µg/kg; s.c.) 60 min before presentation of a test meal led to an elevation of the magnitude of insulin secretion in young rats but reduced the response in aged rats. Moreover, the PIR was not reinstated in aged rats. Blood glucose increments were not influenced by the treatments. The results are interpreted in terms of age-related general reduction of parasympathetic reactivity. The differential effect of amphetamine and AVP treatment on the insulin response suggests that the central aminergic or peptidergic drive of vagal output to the endocrine pancreas is also age-related

Auditoría universitaria y calidad

Consultable des del TDXTítol obtingut de la portada digitalitzadaLa Universidad española tiene en estos momentos ante sí uno de los retos más apasionantes que jamás esta Institución se haya planteado. En primer lugar, la adaptación a los grandes cambios socioeconómicos ocurridos en las últimas décadas que interaccionan desarrollo económico y calidad universitaria. En segundo lugar, como consecuencia de ello, a la búsqueda de la excelencia académica, profesional y científica, que se convierte en un tema clave para la competitividad y la calidad de un país. En tercer lugar, al cambio significativo que ha supuesto la implantación de una armonización universitaria europea a través de la integración y desarrollo en el Espacio Europeo de Educación Superior. Por último, resaltar que el cambio europeo ha quedado sobrepasado por un reto mayor como es la globalización y que ha puesto a las Universidades ya no sólo ante una calidad y competencia europea sino mundial. La calidad y la competitividad de un país no depende solo de la calidad y productividad de sus empresas sino que vendrá determinado en gran parte por la calidad, productividad y competitividad de las Universidades y de sus miembros, tanto en su aspecto investigador como docente. Igualmente el desarrollo económico y del conocimiento de un país tiene mucho que ver con la calidad de la enseñanza de sus universidades. Éstas, al tomar decisiones dentro del ámbito de sus competencias, deberán considerar seriamente su posición competitiva. La Declaración de Bolonia marca las directrices de lo que debe ser la Universidad Europea, de ella se desprende la necesidad de hacer competitiva y atractiva la enseñanza universitaria europea a escala mundial, enfocada a contactar con las necesidades sociales y a hacer más comparables los distintos sistemas educativos. Los Sistemas de Garantía de Calidad son los instrumentos de reforma social y progreso más efectivos que podemos ofrecer en el ámbito universitario, así como una herramienta fundamental para la competitividad y rendición de cuentas. De esta forma se pretende romper con el estereotipo dominante de confundir estos instrumentos con técnicas inherentes y provenientes de la empresa privada en sus manifestaciones más liberales y mercantilistas. En dicho espacio debemos tener en cuenta que el eje mas vertebrado de la armonización van a ser los Sistemas de Garantía de Calidad Universitaria. No podemos olvidar que el cambio europeo ha quedado sobrepasado por un reto mayor, la globalización y que ha situado a las universidades ante una calidad y competencia mundial. No debemos desaprovechar el espacio de educación superior natural, que es Latinoamérica. España tendrá mucho más peso en el Espacio Europeo de Educación Superior si sabe construir rápidamente el Espacio Iberoamericano de Educación Superior. No somos conscientes de que nuestra calidad en Europa depende de que aceleremos el Espacio Iberoamericano dirigido por nosotros mismos con un sistema de evaluación y unos estándares establecidos en ese ámbito Iberoamericano de más de quinientos millones de habitantes de habla española y portuguesa. Esta visión estratégica de acelerar el Espacio Iberoamericano de Educación Superior no es excluyente sino que nos va a reforzar en el Espacio Europeo de Educación Superior y además nos va a servir, como ha sucedido con la experiencia empresarial, para situarnos en la competencia universitaria mundial. Auditoria y evaluación, como a menudo equivocadamente se piensa no es un puro tecnicismo, sino que es un instrumento indispensable para introducir nuevos valores en la sociedad, en el Estado, en la universidad, en la empresa a través de nuevos estándares e indicadores, como son por ejemplo los de calidad ambiental, los de diversidad lingüística y racial en la Universidad, etc. Por tanto la auditoria y evaluación es un sistema muy efectivo de introducir nuevos derechos y valores.The Spanish University has in these moments one of the challenges more exciting that this Institution has never appeared. First, the adjustment to the big socioeconomic changes happened in the last decades that interconnect economic development and university quality. Secondly, as consequence of it, to the search of the academic, professional and scientific excellence, this turns into a key topic for the competitiveness and the quality of a country. Thirdly, to the significant change that has supposed the implantation of a European university harmonization across the integration and development in the European Space of High Education. Finally, to highlight that the European change has remained exceeded by a major challenge as is the globalization and that it has put to the Universities already not only before a quality and European but world competition. The quality and the competitiveness of a country does not depend only on the quality and productivity of its companies but it will come determined largely by the quality, productivity and competitiveness of the Universities and of its members, so much in its investigative as educational aspect. Equally the economic development and of the knowledge of a country there has much that to see with the quality of the education of its universities. These, on having taken decisions inside the area of its competitions, will have to consider seriously its competitive position. The Declaration of Bologna marks the directives what must be the European University, with it there parts the need to make competitive and attractive the university European education on a worldwide scale, focused to contacting with the social needs and to making the different educational systems more comparable. The Systems of guarantee of Quality are the instruments of social reform and progress more workforce that we can offer in the university area, as well as a fundamental tool for the competitiveness and account surrender. Of this form one tries to break with the dominant stereotype of confusing these instruments with technologies inherent and from the private company in its more liberal manifestations and mercantilists. In the above mentioned space we must bear in mind that the axis more vertebrate of the harmonization they are going to be the Systems of Guarantee of University Quality. We cannot forget that the European change has remained exceeded by a major challenge, the globalization and that it has placed to the universities before a quality and world competition. We must not fail to take advantage of the space of top natural education, which is Latin America. Spain will have much more weight in the European Space of High Education if it can construct rapidly the Latin-American Space of High Education. We are not conscious that our quality in Europe depends of that we accelerate the Latin-American Space directed by us themselves with a system of evaluation and a few standards established in this Latin-American area of more than five hundred million inhabitants of Spanish and Portuguese speech. This strategic vision of accelerating the Latin-American Space of High Education is not exclusive but it is going to reinforce us in the European Space of High Education and in addition it is going to serve us, since it has happened with the managerial experience, to place in the university world competition. Audit and evaluation, since often wrongly it is thought is not a pure technicality, but it is an indispensable instrument to introduce new values in the society, in the State, in the university, in the company across new standards and indicators, since they are for example those of environmental quality, those of linguistic and racial diversity in the University, etc. Therefore the audit and evaluation is a very effective system of introducing new rights and values

Socially defeated male rats display a blunted adrenocortical response to a low dose of 8-OH-DPAT

The study examined in male Wistar rats the influence of social defeat on the neuroendocrine stress response system using injection of the 5-HT1A receptor agonist, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), as the pharmacological challenge. Social defeat was defined by the submissive postures displayed by the Wistar rats which were threatened and attacked by Tryon Maze Dull S3 rats for 10 min. 18-20 h after social defeat, the defeated rats were injected intravenously (i.v.) with a low and high dose of 8-OH-DPAT in their home cages. Blood samples were withdrawn from the freely moving cannulated rats for determination of plasma corticosterone and catecholamines. The corticosterone response to the low dose of 8-OH-DPAT (0.05 mg/kg, i.v.) was significantly diminished in the defeated rats as compared to the controls, but this dose failed to affect catecholamine concentrations. The high dose of 8-OH-DPAT (0.15 mg/kg, i.v.) significantly elevated corticosterone and adrenaline levels in defeated and control rats to the same extent, whereas no effect on noradrenaline was found. The present data thus indicate that social defeat blunts 5-HT1A receptor-mediated adrenocortical activation probably via a decrease in the sensitivity of a population of postsynaptic 5-HT receptors

Vasopressinergic modulation of stress responses in the central amygdala of the Roman high-avoidance and low-avoidance rat

The central nucleus of the amygdala (CEA) is selectively involved in the passive component of the behavioral (immobility) and the accompanying parasympathetic response during conditioned, stressful environmental challenges. Vasopressinergic mechanisms in the brain seem to play a role in these stress responses. The effects of the neuropeptides arginine-8-vasopressin (AVP) and oxytocin (OXT) on modulating CEA activity during conditioned stress of inescapable footshock were studied in male Roman high-avoidance (RHA/Verh) and low-avoidance (RLA/Verh) rats, psychogenetically selected on the basis of shuttle-box acquisition behavior. In RLA/Verh rats, the cardiac and behavioral responses to the conditioned emotional stressor were bradycardia and immobility, suggesting an important role for the CEA in these rats. The RHA/Verh rats, however, failed to show any change in heart rate or immobility in response to a conditioned stress situation. The low dose of AVP (20 pg) in the CEA of conscious RLA/Verh rats caused an enhancement of the stress-induced bradycardiac and immobility response. However, the high dose of AVP (2 ng) and OXT (200 pg) attenuated the bradycardiac and immobility responses in the RLA/Verh rats. Infusion of AVP and OXT in the RHA/Verh rats failed to induce any change in heart rate nr immobility. Binding studies revealed that the AVP receptor selectively binds AVP with high affinity. In contrast, the OXT receptor recognizes both AVP and OXT with a similar (but lower) affinity. This suggests that the behavioral and autonomic responses of the high dose of AVP may be caused by OXT receptor stimulation. In conclusion, on the basis of the present results one may hypothesize that CEA differences in AVP and OXT innervation and/or receptor densities may contribute to the differences in coping strategy found in these animals.

Conditioned neuroendocrine and cardiovascular stress responsiveness accompanying behavioral passivity and activity in aged and in young rats

Mean arterial pressure (MAP), heart rate (HR), plasma epinephrine (E), plasma norepinephrine (NE), and plasma corticosterone (CORT) were measured in 3-month- and 24-month-old male Wistar rats exposed to a conditioned emotional stress response (CER) paradigm and a conditioned defensive burying (CDB) paradigm. In the CER situation blood samples were taken during reexposure to the training environment one day after a single inescapable footshock (0.6 mA, AC for 3 s) had been administered. In the CER paradigm the young rats displayed passive behavior (immobility) accompanied by an increase in plasma levels of CORT and E. whereas both the control and conditioned animals showed increased NE responses. Previously shocked aged rats exhibited an attenuated plasma NE response, whereas levels of E remained elevated to a greater extent. Aged animals showed elevated basal levels of CORT one day after footshock administration. Stress-induced immobility was preserved in the aged rats. These animals had an increase in basal MAP values and a decrease in basal HR values compared to young ones.In the CDB paradigm, rats were exposed to a nonelectrified probe 1 day after the repeated shock (2 mA/contact) procedure. Young rats displayed defensive burying accompanied by increments in MAP, HR, CORT. and NE. The aged animals showed similar hormonal, autonomic, and behavioral stress responses.Thus, the age-related alterations in neuroendocrine and autonomic response patterns are apparent in stressed animals during behavioral passivity in absence of control (CER) rather than during active control (defensive burying).</p

Validation of the Spanish version of the borderline symptom list, short form (BSL-23)

Background: The Borderline Symptom List-23 (BSL-23) is a reliable and valid self-report instrument for assessing Borderline Personality Disorder (BPD) severity. The psychometric properties of the original version have proven to be adequate. The aim of the present study was to validate the Spanish language version of the BSL-23. Methods: The BSL-23 was administered to 240 subjects with BPD diagnosis. Factor structure, reliability, test-retest stability, convergent validity, and sensitivity to change were analyzed. Results: The Spanish version of the BSL-23 replicates the one-factor structure of the original version. The scale has high reliability (Cronbach's alpha=.949), as well as good test-retest stability, which was checked in a subsample (n=74; r=.734; p<.01). The Spanish BSL-23 shows moderate to high correlations with depressive symptomatology, state and trait anxiety, hostility and impulsivity scores and BPD measures. The Spanish BSL-23 is able to discriminate among different levels of BPD severity and shows satisfactory sensitivity to change after treatment, which was verified by assessing change before and after 12 group sessions of Dialectical Behavioral Therapy in a subgroup of 31 subjects. Conclusions: Similar to the original BSL-23, the Spanish BSL-23 is a reliable and valid instrument for assessing BPD severity and sensitivity to change