Rat microsomal suspension was prepared using the method
described in our previous paper (Kumar et al., 2011). Briefly, excised
SD rat livers were minced with scissors and homogenized in a solution
composed of 0.32 M sucrose and 1 mM dithiothreitol in 0.02 M
phosphate buffer at pH 6.5. The liver homogenate was further centrifuged
twice at 4500
×
g at 0 ◦C for 30 min each time. All of the
supernatants were collected and kept at
−50 ◦C until used as an
enzyme source.