title: Cellular localization of IL-18 and IL-18 receptor in pig anterior pituitary gland.
abstract: Pro-inflammatory cytokine interleukin 18 (IL-18) has been proposed to have a role in modulating immuno-endocrine functions. Our previous study showed that IL-18 and IL-18 receptor (IL-18R) colocalized in somatotrophs of the bovine anterior pituitary gland, and the possibility that IL-18 acts on somatotrophs as an autocrine factor. In the present study, we investigated the localization of IL-18 and IL-18R in the pig anterior pituitary gland. RT-PCR analysis showed the expression of IL-18 and IL-18R mRNAin the pig anterior pituitary gland. Immunohistochemistry of IL-18 and specific hormones revealed the presence of IL-18 in somatotrophs, mammotrophs, thyrotrophs and gonadotrophs. IL-18R was localized in somatotrophs and thyrotrophs. Furthermore, the somatotrophs immunoreactive for IL-18 did not contain IL-18R. Thus, IL-18R and IL-18 were not colocalized in an identical somatotroph. These findings suggest that the localization of IL-18 in pig somatotrophs is different from that in bovine somatotrophs, although IL-18 closely associates with somatotrophs in the anterior pituitary glands in both species.
authors.affiliation: Laboratory of Functional Morphology, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, 981-8555 Sendai, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nagai
authors.forename: Kouichi
authors.initials: K
authors.lastname: Watanabe
authors.forename: Hisashi
authors.initials: H
authors.lastname: Aso
authors.forename: Shyuichi
authors.initials: S
authors.lastname: Ohwada
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Muneta
authors.forename: Takahiro
authors.initials: T
authors.lastname: Yamaguchi
mesh_terms: D000818:Animals; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D020382:Interleukin-18 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D018123:Receptors, Interleukin / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D053724:Receptors, Interleukin-18; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D013552:Swine / Q000378:metabolism*
chemical_list: D020382:Interleukin-18; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053724:Receptors, Interleukin-18