title: Modulation of mature B cells in mice following treatment with ouabain.
abstract: Ouabain (OUA) is an endogenous hormone released by the adrenal gland under stress situations. Steroid hormones and glucocorticoids have been characterized as selective inhibitors of lymphopoiesis. The present report shows in vivo modulation of mature B cells in bone marrow, spleen and peripheral blood by ouabain. Mice injected intraperitonially (i.p.) with ouabain 0.56 mg/kg for 3 consecutive days displayed, 24 h after last injection, a decreased cellularity in the bone marrow with diminution of the mature B cell subpopulation while the other B cell subpopulations were preserved. Percentually, the myeloid lineage in bone marrow was increased by ouabain. Numbers of mature B lymphocytes in spleen and peripheral blood were reduced following in vivo treatment. In vitro, the B cell populations were not affected. The effects appear to be independent of steroid hormones and strain. The presence of stable levels of glucocorticoids seems to be important because the effects could only be observed from the fourth week animal's life, when glucocorticoid levels are stable. These results open new perspectives for a potential use of ouabain as an immunomodulator.
authors.affiliation: Laboratório de Imunorregulação, Instituto de Biologia, Departamento de Imunobiologia, Universidade Federal Fluminense, Niterói, RJ, Brazil. luspaiva@yahoo.com.br
authors.forename: Luciana S
authors.initials: LS
authors.lastname: de Paiva
authors.forename: Kelli Monteiro da
authors.initials: KM
authors.lastname: Costa
authors.forename: Fabio Barrozo do
authors.initials: FB
authors.lastname: Canto
authors.forename: Vinicius Ribeiro
authors.initials: VR
authors.lastname: Cabral
authors.forename: Rita
authors.initials: R
authors.lastname: Fucs
authors.forename: Alberto
authors.initials: A
authors.lastname: Nobrega
authors.forename: Vivian M
authors.initials: VM
authors.lastname: Rumjanek
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000276:immunology; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D001853:Bone Marrow / Q000187:drug effects* / Q000276:immunology; D002454:Cell Differentiation / Q000187:drug effects* / Q000276:immunology; D019070:Cell Lineage / Q000187:drug effects* / Q000276:immunology; D002478:Cells, Cultured; D005260:Female; D005434:Flow Cytometry; D005938:Glucocorticoids / Q000276:immunology / Q000494:pharmacology; D007155:Immunologic Factors / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D038041:Lymphopoiesis / Q000187:drug effects* / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010042:Ouabain / Q000276:immunology / Q000494:pharmacology*; D013154:Spleen / Q000187:drug effects* / Q000276:immunology
chemical_list: D015703:Antigens, CD; D005938:Glucocorticoids; D007155:Immunologic Factors; D010042:Ouabain