EFFECTS OF β-ENDORPHIN ON PHYTOHEMAGGLUTININ -INDUCED LYMPHOCYTE PROLIFERATION AND MOUSE PLAQUE-FORMINGCELL RESPONSE VIA AN OPIOID RECEPTOR MECHANISM

The effects of opioid peptides on immune responses were investigated.It was found that β-endorphin(β-END) can depress proliferative responses to PHA in rat splenocytes but enhance those in mice,and it could also inibit the plaque-forming cell(PFC) response to sheep red blood cells when mouse splenocytes immunized in vivo were cultured in vitro with the peptide.The peptide antagonist naloxone was able to reverse β-END suppression of the PFC response.The data indicate that β-END suppresses antibody production or secretion via a specific opioidreceptor-mediated mechanism.