title: beta-Endorphin enhances phagocytosis of latex particles in mouse peritoneal macrophages.
abstract: The effects of beta-endorphin (beta End) on phagocytosis in peritoneal macrophages were examined by using flow cytometry (FCM). Beta End enhanced phagocytosis in a dose-dependent manner. Leucine-enkephalin (Leu-Enk), methionine-enkephalin (Met-Enk), alpha-endorphin (alpha End), gamma-endorphin (gamma End), alpha End (18-31) and beta End (28-31) had no such activity. Beta End (1-27) and beta End (6-31) enhanced phagocytosis less effectively than beta End did. Naloxone did not inhibit the enhancement of phagocytosis induced by beta End. Unstimulated control phagocytosis was partially suppressed in Ca2(+)-free EGTA-containing solution and even in this solution beta End enhanced phagocytosis. However, the enhancement was suppressed in the solution containing BAPTA-AM. The present study showed that beta End enhanced extracellular Ca2+ ([Ca2+]o)-dependent and -independent phagocytosis and that the enhancement is largely dependent on intracellular Ca2+ ([Ca2+]i). These results support the contention that beta End is one of the mediators that modulates the immune system.
authors.affiliation: Department of Physiology, Shimane Medical University, Izumo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ichinose
authors.forename: M
authors.initials: M
authors.lastname: Asai
authors.forename: M
authors.initials: M
authors.lastname: Sawada
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000502:physiology; D003593:Cytoplasm / Q000502:physiology; D005110:Extracellular Space / Q000502:physiology; D005260:Female; D007840:Latex; D017737:Macrophages, Peritoneal / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009270:Naloxone / Q000494:pharmacology; D010587:Phagocytosis / Q000187:drug effects*; D013329:Structure-Activity Relationship; D001615:beta-Endorphin / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D007840:Latex; D009270:Naloxone; D001615:beta-Endorphin; D002118:Calcium