title: Hyperbaric oxygen stimulates cell proliferation and normalizes multidrug resistance protein-2 protein localization in primary rat hepatocytes.
abstract: Hyperbaric oxygen therapy (HBO) has been used for many clinical treatments, including primary liver non-function. However, the cellular mechanism by which HBO treatment ameliorates liver function is not understood. Therefore, the purpose of this study was to elucidate this cellular mechanism using primary cultured rat hepatocytes in in vitro studies. Hepatocytes were treated with HBO at 1 day after plating, and the morphological and functional characteristics of bile canaliculi formed in cultured hepatocytes were observed by time-lapse microscopy. Multidrug resistance protein-2 localization was observed by confocal laser microscopy. In cultured hepatocytes, the labeling index in the HBO group at 2 days after treatment was significantly higher than that in the control group. In addition, the proliferating cellular nuclear antigen level in the HBO group was significantly higher than that in the control group. The contraction of the bile canaliculi in the HBO group was slower than in the control group and the dilatation of bile canaliculi in the HBO group was much larger than in the control group. Multidrug resistance protein-2 in the HBO group was localized at the apical membrane. These results show that HBO stimulates hepatocytes to proliferate and HBO normalizes multidrug resistance protein-2 localization to the apical membrane, which could dilate bile canaliculi.
authors.affiliation: Department of Surgery I, Cancer Research Institute, Sapporo Medical University School of Medicine, Sapporo, Japan. tmizu@sapmed.ac.jp
authors.forename: Toru
authors.initials: T
authors.lastname: Mizuguchi
authors.forename: Hideki
authors.initials: H
authors.lastname: Oshima
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Imaizumi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kohara
authors.forename: Masaki
authors.initials: M
authors.lastname: Kawamoto
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nobuoka
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kawasaki
authors.forename: Keisuke
authors.initials: K
authors.lastname: Harada
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Masuda
authors.forename: Yamato
authors.initials: Y
authors.lastname: Kikkawa
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Mitaka
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Asai
authors.forename: Koichi
authors.initials: K
authors.lastname: Hirata
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000032:analysis / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D049109:Cell Proliferation; D002478:Cells, Cultured; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism*; D006931:Hyperbaric Oxygenation; D008297:Male; D018613:Microscopy, Confocal; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D012680:Sensitivity and Specificity; D015854:Up-Regulation; D000097202:ATP-Binding Cassette Sub-Family B Member 4
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000097202:ATP-Binding Cassette Sub-Family B Member 4