Panel a. Expression of CYP4A protein in microsomes prepared from kidneys of control and diabetic rats. Each lane was loaded with 20 μg of protein. *Significant difference from the expression level in the control rats. Panel b. Cytochrome P-450 ω-hydroxylase and epoxygenase activity in microsomes prepared from the kidney of control and STZ-treated diabetic rats chronically treated with vehicle, ABT, or HET0016 for 30 days. The microsomes (0.5 mg protein) were incubated with 14C-AA (0.1 μCi, 42 μM) for 30 min in the presence of NADPH (1 mM). The reactions were stopped with formic acid, extracted with ethyl acetate. The products formed were separated by HPLC and detected using a radioactive flow detector. *Significant difference from the corresponding value in vehicle treated rats, †Significant difference from the corresponding value in non-diabetic control animals.