title: Immunohistochemical and in situ hybridization analysis of galectin-3, a beta-galactoside binding lectin, in the urinary system of adult mice.
abstract: Galectin is an animal lectin that has high affinity to beta-galactoside of glycoconjugates. In the present study, cellular expression of galectin subtypes in the urinary system of adult mice was examined by in situ hybridization and immunohistochemistry. The major subtype expressed in the murine urinary system was galectin-3, which was expressed continuously from the kidney to the distal end of the urethra. The renal cortex expressed galectin-3 more intensely than the medulla. Renal galectin-3 immunoreactivity was strongest in the cortical collecting ducts, where principal cells were the sole cellular source. All cell layers of the transitional epithelium from the renal pelvis to the urethra strongly expressed galectin-3 at the mRNA and protein levels. An electron microscopic study demonstrated diffuse cytoplasmic localization of galectin-3 in principal cells of the collecting ducts and in the bladder epithelial cells. Urethral galectin-3 expression at the pars spongiosa decreased in intensity near the external urethral orifice, where the predominant subtype of galectin was substituted by galectin-7. The muscular layer of the ureter and urinary bladder contained significant signals for galectin-1. Taken together, the observations indicate that the adult urinary system shows intense and selective expression of galectin-3 in epithelia of the uretic bud- and cloaca-derivatives.
authors.affiliation: Laboratory of Anatomy, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18-Nishi 9, 060-0818, Kita-ku, Sapporo, Japan. niojun@vetmed.hokudai.ac.jp
authors.forename: Junko
authors.initials: J
authors.lastname: Nio
authors.forename: Hiromi
authors.initials: H
authors.lastname: Takahashi-Iwanaga
authors.forename: Masami
authors.initials: M
authors.lastname: Morimatsu
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kon
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Iwanaga
mesh_terms: D000818:Animals; D015415:Biomarkers; D037502:Galectin 3 / Q000378:metabolism*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007672:Kidney Cortex / Q000378:metabolism; D007679:Kidney Medulla / Q000378:metabolism; D037102:Lectins; D008297:Male; D051379:Mice; D016253:Microscopy, Immunoelectron; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D014513:Ureter / Q000378:metabolism; D014521:Urethra / Q000378:metabolism; D001743:Urinary Bladder / Q000378:metabolism; D014551:Urinary Tract / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D037502:Galectin 3; D037102:Lectins; D012333:RNA, Messenger