Existence of fatty acyl-CoA oxidizing system in (micro)peroxisomes of rabbit aorta

A cyanide-insensitive palmitoyl-CoA oxidizing activity was detected in rabbit aorta. An assay developed for the arterial acyl-CoA oxidizing system was linear with respect to protein content of the homogenate between 12.5 and 100 micrograms and incubation time for at least 15 min. The system was shown to be localized in (micro)peroxisomes by centrifugation in sucrose density gradient. With a diet containing 1% (w/w) cholesterol and 3% (w/w) olive oil for 8 weeks the activity of peroxisomal beta-oxidation increased from 1.38 to 2.54 nmole/min/g aorta. These results show that the aortic catalase-positive particles have a capacity to oxidize fatty acyl-CoA and participate in fatty acid metabolism.