title: Increased splenocyte proliferative response and cytokine production in beta-endorphin-deficient mice.
abstract: We used beta-endorphin-deficient mice as a novel approach to confirm the physiological role that opioid peptides play in the development or regulation of the immune system. We found that mice lacking beta-endorphin possessed an enhanced immune response, measured in terms of splenocyte proliferation and interleukin (IL)-2 mRNA levels, in vitro production of the splenic macrophage inflammatory cytokines IL-6 and Tumor Necrosis Factor (TNF)-alpha and plasma IL-6 following lipopolysaccharide (LPS) administration. beta-Endorphin-deficient mice had attenuated increases of plasma ACTH and corticosterone levels in response to LPS. These results are consistent with a postulated inhibitory role of endogenous beta-endorphin on the immune system at multiple levels.
authors.affiliation: Laboratorio de Fisiología y Biología Molecular, Departamento de Biología, Facultad de Ciencias Exactas y Naturales (FCEN), Universidad de Buenos Aires, Ciudad Universitaria, Pabellon II, C1428EHA, Buenos Aires, Argentina.
authors.forename: Damian
authors.initials: D
authors.lastname: Refojo
authors.forename: Damian
authors.initials: D
authors.lastname: Kovalovsky
authors.forename: Juan I
authors.initials: JI
authors.lastname: Young
authors.forename: Marcelo
authors.initials: M
authors.lastname: Rubinstein
authors.forename: Florian
authors.initials: F
authors.lastname: Holsboer
authors.forename: Johannes M H M
authors.initials: JM
authors.lastname: Reul
authors.forename: Malcolm J
authors.initials: MJ
authors.lastname: Low
authors.forename: Eduardo
authors.initials: E
authors.lastname: Arzt
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D002455:Cell Division; D002478:Cells, Cultured; D003345:Corticosterone / Q000097:blood; D016207:Cytokines / Q000096:biosynthesis*; D007376:Interleukin-2 / Q000096:biosynthesis / Q000235:genetics; D015850:Interleukin-6 / Q000097:blood; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D012333:RNA, Messenger / Q000096:biosynthesis; D013154:Spleen / Q000166:cytology / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D001615:beta-Endorphin / Q000235:genetics / Q000502:physiology*
chemical_list: D016207:Cytokines; D007376:Interleukin-2; D015850:Interleukin-6; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D001615:beta-Endorphin; D000324:Adrenocorticotropic Hormone; D003345:Corticosterone