title: Hypothermia-dependent and -independent effects of forced swim on the phosphorylation states of signaling molecules in mouse hippocampus.
abstract: Forced swim (FS) stress induces diverse biochemical responses in the brain of rodents. Here, we examined the effect of hypothermia induced by FS in cold water on the phosphorylation of FS-sensitive signaling molecules in the mouse brain. As we have shown previously, FS in cold water induced a significant increase in the level of tyrosine phosphorylation of SIRPα, a neuronal membrane protein, in mouse hippocampus, while such effect of FS was markedly reduced in mice subjected to FS in warm water. FS in cold water also induced phosphorylation of mitogen-activated protein kinase kinase (MEK) as well as of cAMP response element-binding protein (CREB), or dephosphorylation of α isoform of Ca(2+)/calmodulin-dependent protein kinase II (αCaMKII) in the hippocampus. These effects of FS on the phosphorylation of these molecules were also lost in mice subjected to FS in warm water. Genetic ablation of SIRPα did not change the phosphorylation states of these molecules in the brain. Forced cooling of anesthetized mice, which induced a marked increase in the phosphorylation of SIRPα, induced dephosphorylation of αCaMKII in the brain, while the same treatment did not affect the phosphorylation level of MEK and CREB. Hibernation also induced an increase and a decrease of the phosphorylation of SIRPα and αCaMKII, respectively, in the brain of chipmunk. These results suggest that hypothermia is a major element that determines the levels of phosphorylation of αCaMKII and SIRPα during the FS in cold water, while it is not for the phosphorylation levels of MEK and CREB.
authors.affiliation: Laboratory of Biosignal Sciences, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-Machi, Maebashi, Gunma 371-8512, Japan.
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Shinya
authors.initials: S
authors.lastname: Kusakari
authors.forename: Miho
authors.initials: M
authors.lastname: Sato-Hashimoto
authors.forename: Eriko
authors.initials: E
authors.lastname: Urano
authors.forename: Masahiro
authors.initials: M
authors.lastname: Shigeno
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Sekijima
authors.forename: Takenori
authors.initials: T
authors.lastname: Kotani
authors.forename: Yoji
authors.initials: Y
authors.lastname: Murata
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Murakami
authors.forename: Takashi
authors.initials: T
authors.lastname: Matozaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohnishi
mesh_terms: D000818:Animals; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000378:metabolism; D003080:Cold Temperature; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism*; D007035:Hypothermia / Q000378:metabolism*; D007101:Immersion; D020930:MAP Kinase Kinase Kinases / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010766:Phosphorylation; D011971:Receptors, Immunologic / Q000378:metabolism; D013312:Stress, Physiological; D013550:Swimming
chemical_list: C492004:Creb1 protein, mouse; D017362:Cyclic AMP Response Element-Binding Protein; C501922:Sirpa protein, mouse; D011971:Receptors, Immunologic; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D020930:MAP Kinase Kinase Kinases