Abstract
To understand the effects of lipid peroxides on physiological function of small intestine, rat small intestinal mucosa was incubated with 2, 2'-azobis (2-amidinopropane) dihydrochloride (AAPH), a free radical generator in aqueous phase, and changes in the level of lipid peroxidation, protein content, and enzymatic activities of maltase, lactate dehydrogenase (LDH) and mitochondrial dehydrogenase were analyzed. We also examined preventive effects of α-tocopherol and L-ascorbic acid against such changes. Incubation of small intestinal mucosa with AAPH resulted in the increase of thiobarbituric acid reactive substances (TBARS). Similar treatment induced reduction of the maltase activity. Addition of α-tocopherol and L-ascorbic acid prevented the increase of TBARS induced with AAPH, although the inhibitory effect on maltase level did not change unless 500 μg/mg protein of L-ascorbic acid was added. Likewise AAPH lowered the level of LDH and mitochondrial dehydrogenase activities, which was not influenced by α-tocopherol. These results demonstrate that AAPH treatment causes cellular damage, indicating that both lipids and proteins are attacked by free radicals. Further investigation is necessary to clear preventive effects of antioxidative vitamins against change in proteins and cellular injury caused with AAPH in small intestine.
