title: Bidirectional control by glycyrrhizin of the growth response of lymphocytes stimulated through a receptor-bypassed pathway.
abstract: This study demonstrates a unique action of glycyrrhizin (GL) in bidirectionally controlling the growth response of lymphocytes stimulated through a receptor-bypassed pathway by calcium ionophore A23187 and phorbol 12-myristate 13-acetate (PMA). GL up-regulated the response of lymphocytes in vitro to lower concentrations of A23187 and PMA, and down-regulated the response to higher concentrations. We also provide evidence that GL controls the response of lymphocytes of different cell types or maturation stages in different ways, probably because these lymphocytes require different levels of signals as optimum. Finally, the GL-mediated bidirectional controls of the lymphocyte growth response were shown to be adherent cell-independent. The bidirectional controls demonstrated may be significant in normalizing the lymphocyte responses to very weak or very high stimuli.
authors.affiliation: Department of Immunology, Nagoya University School of Medicine, Japan.
authors.forename: Y H
authors.initials: YH
authors.lastname: Zhang
authors.forename: K
authors.initials: K
authors.lastname: Isobe
authors.forename: T
authors.initials: T
authors.lastname: Iwamoto
authors.forename: I
authors.initials: I
authors.lastname: Nakashima
mesh_terms: D000818:Animals; D000001:Calcimycin; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects; D006034:Glycyrrhetinic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D019695:Glycyrrhizic Acid; D008214:Lymphocytes / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D010703:Phorbol Esters; D013154:Spleen / Q000166:cytology; D013950:Thymus Gland / Q000166:cytology
chemical_list: D010703:Phorbol Esters; D000001:Calcimycin; D019695:Glycyrrhizic Acid; D006034:Glycyrrhetinic Acid