Beta-endorphin blunts phosphatidylinositol formation during in vitro activation of isolated human lymphocytes: preliminary report.
We have previously described the regulatory effect of beta-endorphin on three human cytotoxic cell populations. We confirmed the variable nature of these effects on human natural killer cell (NK) activity, showed mixed effects on the generation of cytotoxic T lymphocyte (CTL) activity, and demonstrated the reproducible suppression of lymphokine-activated killer cell (LAK) activity. We and others also observed mixed effects of beta-endorphin on the proliferative response to mitogens and in mixed leukocyte reactions. In the study reported here, we test the effects of beta-endorphin on the formation of phosphatidylinositol during cell activation. 32P-radiolabeled peripheral blood mononuclear cells obtained from normal adult donors and CD2-depleted subpopulations were activated with phytohemagglutinin or in a NK, LAK, or CTL protocol in the absence or presence of recombinant beta-endorphin. The total lipidic extract was analyzed by thin-layer chromatography and autoradiography. The results of these studies indicate that beta-endorphin blunts the formation of phosphatidylinositol by about 20% in the four systems studied and in all the donors tested. This effect is dose-dependent and is blocked in part by the opioid antagonist, naltrexone, suggesting involvement of the opioid receptor.
Chiappelli
F
F
Psychoneuroimmunology Program, University of California, Los Angeles 90024.
Nguyen
L
L
Bullington
R
R
Fahey
J L
JL
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D015979:Killer Cells, Lymphokine-Activated / Q000187:drug effects*; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009271:Naltrexone / Q000494:pharmacology; D010716:Phosphatidylinositols / Q000378:metabolism*; D010835:Phytohemagglutinins; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D001615:beta-Endorphin / Q000494:pharmacology*
D010716:Phosphatidylinositols; D010835:Phytohemagglutinins; D009271:Naltrexone; D001615:beta-Endorphin