title: Kupffer cells alter organic anion transport through multidrug resistance protein 2 in the post-cold ischemic rat liver.
abstract: Although Kupffer cells (KCs) may play a crucial role in post-cold ischemic hepatocellular injury, their role in nonnecrotic graft dysfunction remains unknown. This study examined reveal the role of KC in post-cold ischemic liver grafts. Rat livers treated with or without liposome-encapsulated dichloromethylene diphosphonate, a KC-depleting reagent, were stored in University of Wisconsin (UW) solution at 4 degrees C for 8 to 24 hours and reperfused while monitoring biliary output and constituents. The ability of hepatocytes to excrete bile was assessed through laser-confocal microfluorography in situ. Cold ischemia-reperfused grafts decreased their bile output significantly at 8 hours without any notable cell injury. This event coincided with impaired excretion of glutathione and bilirubin-IXalpha (BR-IXalpha), suggesting delayed transport of these organic anions. We examined whether intracellular relocalization of multidrug resistance protein-2 (Mrp2) occurred. Kinetic analyses for biliary excretion of carboxyfluorescein, a fluoroprobe excreted through this transporter, revealed significant delay of dye excretion from hepatocytes into bile canaliculi. The KC-depleting treatment significantly attenuated this decline in biliary anion transport mediated through Mrp2 in the 8-hour cold ischemic grafts via redistribution of Mrp2 from the cytoplasm to the canalicular membrane. Furthermore, thromboxane A(2) (TXA(2)) synthase in KC appeared involved as blocking this enzyme improved 5-carboxyfluorescein excretion while cytoplasmic internalization of Mrp2 disappeared in the KC-depleting grafts. In conclusion, KC activation is an important determinant of nonnecrotic hepatocellular dysfunction, jeopardizing homeostasis of the detoxification capacity and organic anion metabolism of the post-cold ischemic grafts.
authors.affiliation: Department of Hepatobiliary Pancreatic Surgery, School of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kudo
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kashiwagi
authors.forename: Mayumi
authors.initials: M
authors.lastname: Kajimura
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Yoshimura
authors.forename: Koji
authors.initials: K
authors.lastname: Uchida
authors.forename: Shigeki
authors.initials: S
authors.lastname: Arii
authors.forename: Makoto
authors.initials: M
authors.lastname: Suematsu
mesh_terms: D018528:ATP-Binding Cassette Transporters; D000818:Animals; D001646:Bile / Q000378:metabolism; D001663:Bilirubin / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism*; D003080:Cold Temperature; D015925:Cryopreservation; D005452:Fluoresceins / Q000493:pharmacokinetics; D005978:Glutathione / Q000378:metabolism; D007511:Ischemia / Q000378:metabolism*; D007728:Kupffer Cells / Q000378:metabolism*; D008099:Liver / Q000166:cytology / Q000378:metabolism; D016031:Liver Transplantation; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013931:Thromboxanes / Q000096:biosynthesis
chemical_list: D018528:ATP-Binding Cassette Transporters; C423013:Abcc2 protein, rat; D002352:Carrier Proteins; D005452:Fluoresceins; D013931:Thromboxanes; C045132:4-carboxyfluorescein; D005978:Glutathione; D001663:Bilirubin