Changes in conjugated dienes (A) or MDA-modified LDL (B) induced by copper ions in control, diabetic, and pravastatin-treated diabetic rats, and by incubation with pravastatin in vitro. (A) Formation of conjugated dienes analysed by continuous monitoring of change of absorbance at 234 nM in samples containing 25 μg protein ml−1. (B) To measure MDA levels, LDL were incubated to a final concentration of 0.2 mg protein ml−1 with 10 μM CuSO4 at 37°C for 0, 4, or 24 h. Each data point represents mean±s.e.mean of 4–8 experiments; the s.e. is included only when it exceeds the dimension of the symbol used. *P<0.05, ***P<0.001, diabetic vs control; ††P<0.01, diabetic vs pravastatin-treated diabetic.