ROLE OF HEPATOVASCULATURE IN WARM ISCHEMIA-REPERFUSION INJURY OF RAT-LIVER

Liver haemodynamics were studied after warm (37 degrees C) ischaemia o f isolated rat livers for periods of 30 s (Group 1), 30 min (Group 2), and 60 min (Group 3) using a constant pressure system with a recircul ating blood-free perfusate. Portal flow recovered to basal values with in 6 min in livers from Group 1, whereas it was significantly reduced in Group 2 during the initial 15 min and in Group 3 during the first 3 3 min of reperfusion. Thus, the recovery of liver flow was proportiona l to the duration of ischaemia. By using the same mode of liver perfus ion, the effect of norepinephrine on portal resistance was also studie d in normal livers At the beginning of reperfusion, the values of port al resistance in ischaemic livers were comparable to the values of por tal resistance mediated by norepinephrine at concentrations between 10 (-7) and 10(-6) mol/l in normal livers. The results suggest that vasoc onstriction of the hepatovasculature may be a contributing factor to t he reperfusion injury of the liver following warm ischaemia.