Combinative ligand‐receptor interactions: Epinephrine depresses RAW264 macrophage antibody‐dependent phagocytosis in the absence and presence of met‐enkephalin

Howard R. Petty, Kelly A. Berg

Research output: Contribution to journalArticle

21 Scopus citations

Abstract

Macrophages have been shown to possess cell surface receptors for opiates and catecholamines. The abilities of these ligands to affect RAW264 macrophage antibody‐dependent effector activity directed against sheep red blood cells were tested. Phagocytosis was measured by the uptake of 51Cr labeled erythrocytes and optical microscopy. Cytolysis was measured by 51Cr‐release assays. Met‐enkephalin increased specific antibody‐dependent phagocytosis in a dose‐dependent fashion; the optimal dose was found to be 10−8 M. Epinephrine diminished phagocytosis in a dose‐dependent manner exhibiting a maximal inhibition at 10−4–10−5 M. This inhibition can be blocked by propranolol. The combined effects of simultaneous treatment with met‐enkephalin and epinephrine were measured. At the several doses tested, the combined effects of these two ligands on the amount of phagocytosis were equivalent to or more inhibitory than epinephrine alone. Thioglycolate‐elicited murine peritoneal macrophages demonstrated similar responses to epinephrine, met‐enkephalin, and their combination. Therefore, in vitro models more closely approximating in vivo neuroregulation of macrophage function demonstrate phagocytic inhibition.

Original languageEnglish (US)
Pages (from-to)281-286
Number of pages6
JournalJournal of Cellular Physiology
Volume134
Issue number2
DOIs
StatePublished - Feb 1988

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ASJC Scopus subject areas

  • Physiology
  • Clinical Biochemistry
  • Cell Biology

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