(a)
(b)
Figure 6: Effects of calcium and of antagonists of calcium channels on enzyme release by perfused isolated livers and liver slices from PH rats. Results of enzyme activities are expressed as mean ± SE (six independent determinations per experimental point) of times over liver preparations under basal conditions (no added calcium and a flow rate of 2 mL⋅min−1⋅g−1 of liver). Basal values for released liver enzymes were for LDH, ALT, GDH, and OCT = 7, 5, 1.2, and 4.1 mU⋅min−1⋅g−1 of liver, respectively. The additions to the perfusion medium were 2 mmol/L calcium, 30 μmoles/L verapamil, or 15 μmoles/L diltiazem, and the flow rate increased to 6 mL⋅min−1⋅g−1 of liver. At the bottom, liver slices were subjected to the same conditions. Experimental groups are as indicated at the top of the figure. Statistical significance: against the basal condition (without calcium) and versus enzyme release under increased flow rate in the presence of 1.8 mmoles/L calcium.