Endorphins stimulate normal human peripheral blood lymphocyte natural killer activity

Neil Kay, John Allen, John E. Morley

Research output: Contribution to journalArticlepeer-review

165 Scopus citations


Opioid peptides are present in peripheral blood, and may bind to human lymphocytes. In order to determine their influence on human lymphocytes we studied the effect of endogenous opioid peptides on human lymphocyte natural killer function. Beta-endorphin and several analogues (i.e., γ-endorphin) are shown to enhance human peripheral blood natural killer function. The enhancement of natural killing by these opioid peptides was dose-dependent and naloxone (an opiate antagonist) reversible. In studying various analogues of β-endorphin, β-lipotropin and γ-endorphin were approximately 3-5 times more effective at enhancing peripheral blood NK function than Leu-enkephalin and -endorphin. In addition, we observed that naloxone reversed human fibroblast interferon mediated enhancements of human blood lymphocyte natural killer function. These observations suggest that circulating endogenous opioid peptides may have a physiologic role in regulating human blood lymphocyte natural killing.

Original languageEnglish (US)
Pages (from-to)53-59
Number of pages7
JournalLife Sciences
Issue number1
StatePublished - Jul 2 1984

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Pharmacology, Toxicology and Pharmaceutics(all)


Dive into the research topics of 'Endorphins stimulate normal human peripheral blood lymphocyte natural killer activity'. Together they form a unique fingerprint.

Cite this