Atrial natriuretic peptide preconditioning protects against hepatic preservation injury by attenuating necrotic and apoptotic cell death.
OBJECTIVE
Preconditioning of livers with the atrial natriuretic peptide (ANP) markedly reduces hepatic ischemia-reperfusion injury. Aim of this study was to characterize the influence of ANP preconditioning on necrotic and apoptotic cell death and on proliferation.


METHODS
Rat livers were perfused with Krebs-Henseleit buffer with or without ANP or its second messenger analogue 8-Bromo cyclic guanosine monophosphate (8-Br cGMP) for 20 min, stored in cold University of Wisconsin solution (24 h), and reperfused for up to 120 min. Apoptosis and necrosis were determined using biochemical and morphological criteria, proliferation was assessed by Ki67 histochemistry.


RESULTS
Apoptosis peaked after 24 h of cold ischemia. Preconditioning with both ANP and 8-Br-cGMP significantly reduced caspase-3-like activity and the number of triphosphate nick-end labelling-positive cells. Reduction of apoptosis was significant for hepatocytes, but not for endothelial cells. After ischemia, degenerative cell changes were clearly reduced in ANP pretreated livers. After reperfusion, ANP preconditioning led to a significant reduction of necrotic hepatocytes and endothelial cells in periportal zones. Cell proliferation was not affected by preconditioning.


CONCLUSIONS
ANP reduces necrotic and apoptotic cell death without affecting the proliferation status. The protection takes place mainly in the periportal area and seems to be most prominent against necrosis of hepatocytes and endothelial cells during reperfusion.
Gerwig
Tobias
T
Department of Pharmacy, Center of Drug Research, University of Munich, Klinikum Grosshadern, Marchioninistrasse 15, D-81377 Munich, Germany.
Meissner
Herbert
H
Bilzer
Manfred
M
Kiemer
Alexandra K
AK
Arnholdt
Hans
H
Vollmar
Angelika M
AM
Gerbes
Alexander L
AL
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D053148:Caspase 3; D061945:Caspase Inhibitors; D002455:Cell Division / Q000187:drug effects; D003213:Conditioning, Psychological; D015925:Cryopreservation; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000494:pharmacology; D020287:In Situ Nick-End Labeling; D008099:Liver / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D009336:Necrosis; D009926:Organ Preservation / Q000009:adverse effects*; D051381:Rats; D017207:Rats, Sprague-Dawley
D061945:Caspase Inhibitors; C016276:8-bromocyclic GMP; D009320:Atrial Natriuretic Factor; C505410:Casp3 protein, rat; D053148:Caspase 3; D006152:Cyclic GMP