Immune deviation following stress odor exposure: role of endogenous opioids

Olfactory cues can alter immune function. BALB/c mice exposed to odors prod uced by footshock stressed donor mice have increased antibody responses and increased splenic interleukin (IL)-4 production following immunization rel ative to recipients of odors from unstressed animals. Here we document that exposure to stress odors results in analgesia that is blocked by the non-s elective opioid receptor antagonist naltrexone. The stress odor-induced inc rease in antigen-driven IL-4 and antibody is also blocked by oral administr ation of naltrexone. Thus, we provide evidence that immune deviation can oc cur following a psychosocial stressor, and that the deviation appears to be mediated by endogenous opioid production. (C) 2000 Elsevier Science B.V. A ll rights reserved.