title: Effect of mild hypothermia on the expression of aquaporin family in cultured rat astrocytes under hypoxic condition.
abstract: Aquaporins (AQPs) are a family of water-selective transporting proteins with homology to the major intrinsic protein (MIP) of lens, that increase plasma membrane water permeability in secretory and absorptive cells. In this study, we investigated the effect of mild hypothermia on the expression of AQP4, AQP5 and AQP9 in rat astrocytes cultured under hypoxic conditions. At 37 degrees C, a marked decrease in the expression of AQP4, AQP5 and AQP9 mRNAs was observed. However, at 32 degrees C (mild hypothermia), the expression of AQP5 mRNA was restored to its basal level. Interestingly, under mild hypothermia AQP4 mRNA expression transiently decreased and then increased about two-fold; while AQP9 mRNA expression decreased the same as at 37 degrees C. The changes in the expression of AQP4 and AQP9 proteins were confirmed by Western blot analysis. The restoration of the AQP4 and AQP5 expression at 32 degrees C from the hypoxia-induced decrease at 37 degrees C may play an important role in the reduction of brain edema under hypothermic conditions.
authors: Department of Anesthesiology and Medical Crisis Management, Nagoya City University Graduate School of Medical Sciences, Mizuho-ku, Nagoya 467-8901, Japan.
authors: Yoshihito
authors: Y
authors: Fujita
authors: Naoki
authors: N
authors: Yamamoto
authors: Kazuya
authors: K
authors: Sobue
authors: Masaaki
authors: M
authors: Inagaki
authors: Hiroaki
authors: H
authors: Ito
authors: Hajime
authors: H
authors: Arima
authors: Tetsuro
authors: T
authors: Morishima
authors: Akinori
authors: A
authors: Takeuchi
authors: Takako
authors: T
authors: Tsuda
authors: Hirotada
authors: H
authors: Katsuya
authors: Kiyofumi
authors: K
authors: Asai
mesh_terms: D000818:Animals; D020346:Aquaporins / Q000096:biosynthesis*; D001253:Astrocytes / Q000502:physiology*; D015153:Blotting, Western; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D007036:Hypothermia, Induced; D000860:Hypoxia / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D020346:Aquaporins; D012333:RNA, Messenger