|
|
||||||||
1 Medical Department A, National University Hospital, 2100 Ø Copenhagen, Denmark; and 2 Marion Bessin Liver Research Center, Albert Einstein College of Medicine, New York, New York 10461
Lipopolysaccharide (LPS) initiates cholestasis. Whether this
process is mediated by tumor necrosis factor-
(TNF-
) and whether the cholestatic response to LPS is associated with intrahepatic accumulation of possibly toxic substances are under debate. To study
these questions the hepatic uptake and biliary excretion of indocyanine
green (ICG) was examined in the isolated perfused rat liver 18 h after
intravenous treatment of rats with either saline, 1 mg/kg body wt LPS,
or LPS and intraperitoneal pentoxifylline (POF) (n = 6 in
each group). POF inhibits TNF-
release after LPS administration. LPS
induced a typical acute-phase response with increased mRNA for
acute-phase proteins, reduced albumin mRNA, and increased hepatic
uptake of alanine. Intrinsic hepatic clearance of ICG in controls
(1.01 ± 0.05 ml · min
1 · g
liver
1) was similarly decreased by LPS alone
(0.62 ± 0.04
ml · min
1 · g
1;
P = 0.002 vs. control) or combined with POF (0.66 ± 0.06
ml · min
1 · g
1).
A kinetic analysis indicated that LPS reduced both uptake and excretion
processes in a balanced manner, so that intrahepatic ICG content was
unaffected or even slightly reduced, as confirmed by measurement of ICG
contents in the perfused livers. In livers from parallel-treated
nonperfused rats, mRNA for the organic anion transporting protein-1
(Oatp1, which is likely to mediate ICG uptake) was unaffected by LPS,
whereas the concentration of Oatp1 protein was reduced. Thus LPS
induced an acute-phase response that included downregulation of ICG
uptake by reduction of Oatp1 protein concentration, possibly at a
posttranscriptional level. TNF-
appears not to be the mediator
because POF did not modify these LPS effects.
Oatp1; cytokines; acute-phase response; endotoxin; tumor necrosis
factor-
; lipopolysaccharide
This article has been cited by other articles:
![]() |
A. Geier, C. G. Dietrich, S. Voigt, M. Ananthanarayanan, F. Lammert, A. Schmitz, M. Trauner, H. E. Wasmuth, D. Boraschi, N. Balasubramaniyan, et al. Cytokine-dependent regulation of hepatic organic anion transporter gene transactivators in mouse liver Am J Physiol Gastrointest Liver Physiol, November 1, 2005; 289(5): G831 - G841. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Hartmann, A. K. Y. Cheung, and M. Piquette-Miller Inflammatory Cytokines, but Not Bile Acids, Regulate Expression of Murine Hepatic Anion Transporters in Endotoxemia J. Pharmacol. Exp. Ther., October 1, 2002; 303(1): 273 - 281. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. W. A. Beno, M. R. Uhing, M. Goto, Y. Chen, V. A. Jiyamapa-Serna, and R. E. Kimura Endotoxin-induced reduction in biliary indocyanine green excretion rate in a chronically catheterized rat model Am J Physiol Gastrointest Liver Physiol, May 1, 2001; 280(5): G858 - G865. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. W. A. Beno, M. R. Uhing, M. Goto, Y. Chen, V. A. Jiyamapa-Serna, and R. E. Kimura Staphylococcal enterotoxin B potentiates LPS-induced hepatic dysfunction in chronically catheterized rats Am J Physiol Gastrointest Liver Physiol, May 1, 2001; 280(5): G866 - G872. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |