33. Neuroendocrine modulation of the immune system by repeated anticipation in domestic pigs

• Published in: Brain, behavior, and immunity Vol. 32; p. e10
• Main Authors: Brietzke, J, Jaskulke, S, Kanitz, E, Tuchscherer, M, Otten, W, Schön, P.C, Tuchscherer, A, Manteuffel, G, Gimsa, U
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2013
• Subjects: Allergy and Immunology; Psychiatry
• ISSN: 0889-1591; 1090-2139
• DOI: 10.1016/j.bbi.2013.07.045

Emotional states may modulate immune functions. We used a model of repeated positive (food), negative (air-puff) or conflicting anticipation (food or air-puff) in domestic pigs in order to induce a change in mood over a treatment period of 4 weeks. Anticipation was triggered by a sound while controls received the same stimuli not preceded by a sound or no stimulus. Changes in heart rate and heart rate variability during the sound indicated repeated arousal involving the sympathetic nervous system only in the positively anticipating group. These animals also showed an increased serotonin turnover in the ventral tegmental area. Investigation of hypothalamic–pituitary–adrenal axis responses revealed a habituation of the animals to the experimental housing and procedure but no specific treatment effects. Also, gene expression of CRH and GR in limbic areas was not influenced by treatment indicating that the animals did not experience stress. However, immunological analyses revealed a reduced T-cell proliferation in response to the mitogen staphylococcal enterotoxin B and a less pronounced age-dependent increase of serum IgM concentrations in pigs with repeated positive anticipation. Our data suggest that repeated positive anticipation may induce a state of arousal that may slightly down-modulate immune functions without the induction of typical stress responses.