ABSTRACT
Behavioral medicine has long been interested in the interaction of emotions, stress, and susceptibility to infection. Reviewing the literature on stress and tumors reveals a picture similar to that relating stress and infection. Stress is associated with alterations of humoral and cellular immune mechanisms in both laboratory animals and humans. Stress can, by its potent neural, neurochemical, and neurohormonal effects, alter the susceptibility of animals to a wide variety of diseases, including neoplasia, possibly by altering immune function. Morphine and opioid peptides released by stress might suppress immune function by acting directly on opiate receptors present on various cells of the immune system. The chapter reports that a single exposure to the opioid form of foot shock stress or a single high dose of morphine induces suppression of natural killer (NK) cell cytotoxicity. Numerous reports suggest that immune surveillance against viral infections and neoplastic disease is primarily provided by cytotoxic T lymphocytes and NK cells.
