CALCIUM IN PIG LIVERS FOLLOWING ISCHEMIA AND REPERFUSION

Calcium concentrations in pig livers were serially estimated following ischemia-reperfusion. Ischemia was produced by clamping the hepatic a rtery and the portal vein for 90 min (Group 1, n=6) or for 180 min (Gr oup 2, n=6) during temporary side-to-side portacaval shunt performed b efore the induction of ischemia. Although there were no significant ch anges in hepatic calcium concentrations during ischemia, an immediate accumulation of calcium occurred 30 min after reperfusion in both grou ps. After these increases, the hepatic calcium concentration decreased to near the pre-ischemic level within 20 min in all animals in Group 1. The recovery of calcium was incomplete in Group 2. When the peak wa s defined as the highest level of calcium and the bottom as the lowest point after peak 60 min after reperfusion, the mean-peak was 11.0+/-1 .3 (mean+/-SEM) nmol/mg dry weight liver in Group 1 and 12.8+/-1.4 nmo l/mg dry weight liver in Group 2 (not significant). However, the mean- bottom in Group 1 was lower than that in Group 2 (5.5+/-0.3 and 8.1+/- 0.8 nmol/mg dry weight liver, respectively, p<0.05). These results ind icate that hepatic calcium increases immediately after reperfusion and that recovery from this calcium accumulation seems to be a crucial fa ctor for minimizing cellular injury. (C) Journal of Hepatology.