Segmental ischemia of the liver - microdialysis in a novel porcine model.
BACKGROUND
Segmental liver ischemia is often used in rodents to study ischemia and reperfusion injuries (IRI). There are no reports of protocols using segmental ischemia in porcine models. Microdialysis (MD) provides the opportunity to study local effects of IRI in vivo.


METHODS
Eight pigs received an MD catheter placed in liver segments IV and V, respectively. All circulation to segment IV was stopped for 80 min, and reperfusion was followed for 240 min.


RESULTS
During ischemia the levels of lactate, glycerol and glucose increased 3-fold (p < 0.001), 40-fold (p < 0.001) and 4-fold (p < 0.01), respectively, in the ischemic segment compared to the perfused segment, whereas the levels of pyruvate fell to a tenth of the preischemic level (p < 0.001). All values returned to baseline after reperfusion. Serum levels of aspartate aminotransferase increased (p < 0.05). Polymorphonuclear cells increased in both segments, although the density was significantly higher in segment IV.


CONCLUSIONS
Clamping of one liver segment in pigs is a simple, stable and reproducible model to study IRI with minimal systemic effects. MD revealed no signs of anaerobic metabolism in the perfused segment but still there was an increase in the number of polymorphonuclear neutrophils in this segment, although it was lower than that in the ischemic segment.
Winbladh
Anders
A
Department of Surgery, University Hospital, Linköping, Sweden. anders.winbladh@lio.se
Sandström
P
P
Olsson
H
H
Svanvik
J
J
Gullstrand
P
P
D000818:Animals; D004195:Disease Models, Animal; D017078:Laser-Doppler Flowmetry; D008099:Liver / Q000098:blood supply / Q000473:pathology; D008107:Liver Diseases / Q000378:metabolism* / Q000473:pathology; D008297:Male; D017551:Microdialysis; D015427:Reperfusion Injury / Q000378:metabolism* / Q000473:pathology; D013552:Swine