... established and are summarised in Table 3. IMMUNOSUPPRESSION – ROLE IN HEALTH AND DISEASES Edited by Suman Kapur and Maristela Barbosa Portela Immunosuppression – Role in Health and Diseases ... work by binding to opioid receptors, found in the central and peripheral nervous system and the gastrointestinal tract. Opioids play diverse biological functions, including reward, analgesia, and ... cells and inflammation mediator gene/s expression and secretion (Shin and Masato, 2008). In turn, the major source of local endogenous opioid ligands (beta-endorphin, enkephalins, endomorphins and...