+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found

      The Effects of a Switch-Off Response Accompanied by Hypothalamically Induced Restlessness on Immunoendocrinological Changes in Cats

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          Electrical stimulation of the anterior hypothalamus in cats elicits a behavior called restlessness. When a switch is available for the cats to shut off the electrical stimulation, the cats learn to turn off the stimulation (switch-off response; SOR). In this study, we examined the relationship between the SOR and immunoendocrinological alterations. First of all, an escapable stimulation, in which cats could turn off the stimulation, was applied (escapable condition; EC). One month later, inescapable stimulation was delivered under the same conditions except for the fact that the cats could not turn off the stimulation (inescapable condition; IC). A behavioral analysis revealed that unstable patterns of behavior and a reduction in motor activity were observed in IC compared with those in EC. Furthermore, no significant changes in peripheral leukocytes were observed, while plasma epinephrine and cortisol transiently increased after the series of stimulations, but immediately decreased after the end of the stimulation in EC. On the other hand, there was a greater and prolonged increase in the number of peripheral granulocytes and the plasma levels of epinephrine and cortisol from 1 to 2 h after the stimulation until the end of the experiment in IC. Regarding the number of peripheral lymphocytes, CD4+ or CD8+ lymphocytes and the CD4+ to CD8+ ratio, no significant differences were found between EC and IC. These results suggest that the inability to escape from the aversive stimulation caused a decrease in movement and a prolonged alteration of the immune and endocrine systems, as is often observed in learned helplessness.

          Related collections

          Most cited references 10

          • Record: found
          • Abstract: found
          • Article: not found

          Plasma catecholamine and corticosterone levels during active and passive shock-prod avoidance behavior in rats: effects of chlordiazepoxide.

          Plasma noradrenaline (NA), adrenaline (A) and corticosterone (CS) concentrations were determined in rats before, during and after 15-min exposure to a constantly electrified (2 mA) or nonelectrified prod which was mounted on the wall of the home cage either with or without bedding material on the floor. Concomitantly, exploration of the prod, freezing and prod-burying behavior were recorded. Both in the presence and absence of bedding material, rats explored the nonelectrified prod and showed a small increase in plasma NA and CS contents. Exploration of the prod was strongly reduced when the prod was electrified. In the presence of bedding material, shocked rats typically displayed burying behavior (active avoidance), whereas in the absence of bedding (i.e., burying option eliminated) shocked rats engaged in freezing behavior (passive avoidance). The passive avoidance situation was accompanied by larger A and CS increases but a lower NA rise as compared to the hormonal responses associated with the active avoidance situation. Administration of the anxiolytic chlordiazepoxide (CDP; 9 mg/kg intragastrically) attenuated the shock-induced suppression of prod exploration, decreased prod-burying behavior but, paradoxically, increased freezing behavior. Irrespective of bedding condition, the prod shock-induced elevations in plasma CS and A contents were completely abolished in CDP-treated rats. The rise in plasma NA was attenuated only in CDP-treated rats tested on a bedding-floor. The results indicate that passive (e.g., freezing) and active (e.g., burying) behavioral coping are each accompanied by specific and dissociated patterns of neurosympathetic, adrenomedullary and adrenocortical outflow. CDP-treatment shifts an animal's behavioral coping style from an active to a passive form of avoidance responding, but abolishes the accompanying adrenocortical and adrenomedullary activation.
            • Record: found
            • Abstract: not found
            • Article: not found

            Influence of stressor predictability and behavioral control on lymphocyte reactivity, antibody responses and neuroendocrine activation in rats

              • Record: found
              • Abstract: found
              • Article: not found

              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).

                Author and article information

                S. Karger AG
                February 2004
                06 February 2004
                : 11
                : 2
                : 103-112
                Departments of aNeuropsychiatry and bPsychosomatic Medicine, Graduate School of Medical Science, Kyushu University, Fukuoka City, Japan
                75319 Neuroimmunomodulation 2004;11:103–112
                © 2004 S. Karger AG, Basel

                Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

                Page count
                Figures: 6, Tables: 1, References: 45, Pages: 10
                Original Paper


                Comment on this article