LIPID PEROXIDATION OF MICROSOMES OBTAINED FROM RAT LIVER AND KIDNEY: EFFECT OF CIS-9, TRANS-11-CONJUGATED

unlp.edu.ar The polyunsaturated fatty acid composition, chemiluminescence and peroxidizability index of microsomes obtained from rat liver and kidney were studied after oral administration of cis-9, trans-11-conjugated linoleic acid isomer (c9-t11-CLA). After incubation of microsomes in an ascorbate Fe++ system (120 min at 37°C) it was observed that the total counts per min/mg protein originated from light emission: chemiluminescence was lower in liver and kidney microsomes in the c9-t11-CLA group than in the microsomes obtained from control group. The effect of c9-t11-CLA on the polyunsaturated fatty acid composition of native liver microsomes was evidenced by a statistically signifi cant p<0.007 decrease of linoleic acid C18:2 n6. When peroxidized microsomes obtained from liver and kidney of both groups (control and c9-t11-CLA) were compared with respective natives, it was observed that C18:2 n6, C20:4 n6 decreased in all membranes used in this work, whereas in microsomes obtained from liver c9-t11-CLA and control groups C22:6 n3 also decreased. As a consequence, the peroxidizability index – a parameter based on the maximal rate of oxidation of fatty acids – showed signifi cant changes in liver and kidney microsomes. These changes were less pronounced in membranes derived from rats receiving c9-t11-CLA per os. Our results would confi rm and extend previou