Carnitine acyltransferases are not changed in Alzheimer disease

We evaluated the activities of carnitine palmitoyltransferase (CPT), carnit ine octanoyltranferase (COT), and carnitine acetyltransferase (CAT) in the frontal cortex, temporal cortex, parietal cortex, hippocampus, and cerebell um of Alzheimer disease (AD) patients and normal human brains. There were n o significant differences in total CPT activity, its inhibition by malonyl- CoA, the effect of the detergent Triton X-100 on CPT activity, COT activity , and CAT activity in any of the brain regions examined, whether activities were expressed as grams of wet weight or corrected for noncollagen protein content. The addition of Triton X-100 increased CAT activity by 50%. Our r esults suggest that there is no defect of fatty acid transport within the A D brain cell. Total CPT activity, COT activity, and CAT activity are not af fected in AD nor is the ratio of CPT I to CPT II altered in the AD versus t he normal human brain.