title: Systemic administration of lipopolysaccharide increases the expression of aquaporin-4 in the rat anterior pituitary gland.
abstract: We investigated the effects of lipopolysaccharide (LPS)-induced endotoxemia on the expression of aquaporin-4 (AQP4) in the rat anterior pituitary gland, using the real-time polymerase chain reaction and immunohistochemistry. After intraperitoneal injection of LPS, the level of AQP4 mRNA doubled at 2, 4 and 8 hr. Immunohistochemical analysis showed an increase with time in AQP4 immunostaining in folliculo-stellate cells following LPS injection; the intensity of immunoreactivity peaked at 8 hr. At the same time, some cyst-like structures, formed by AQP4-positive cells, were observed. These findings indicate that LPS induces the expression of AQP4 in the anterior pituitary gland. The present results should provide an important key to elucidate the pathogenesis of the anterior pituitary gland during endotoxemia.
authors.affiliation: Department of Anatomy and Cell Biology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501, Japan.
authors.forename: Sachi
authors.initials: S
authors.lastname: Kuwahara-Otani
authors.forename: Seishi
authors.initials: S
authors.lastname: Maeda
authors.forename: Koichi
authors.initials: K
authors.lastname: Tanaka
authors.forename: Tetsu
authors.initials: T
authors.lastname: Hayakawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Seki
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D051401:Aquaporin 4 / Q000378:metabolism*; D019446:Endotoxemia / Q000139:chemically induced / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D007150:Immunohistochemistry; D008070:Lipopolysaccharides / Q000633:toxicity*; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction
chemical_list: C496032:Aqp4 protein, rat; D051401:Aquaporin 4; D008070:Lipopolysaccharides