Skip to main content
Open Access Publications from the University of California

UC Irvine

UC Irvine Previously Published Works bannerUC Irvine

Ornithine decarboxylase activity associated with a particulate fraction of brain.


The enzymic decarboxylation of ornithine by adult rat brain largely occurs in the particulate fraction. The activity is primarily due to ornithine decarboxylase (ODC) as evidenced by several criteria: the concurrent production of equimolar amounts of CO2 and putrescine, the sensitivity of the reaction to difluoromethylornithine (DFMO), a specific inhibitor of ODC, the lack of major effect of two inhibitors of ornithine-2-oxo-acid transaminase, upon the DFMO-sensitive component of decarboxylation, the failure to profoundly reduce decarboxylation activity in the presence of a large excess of many aminoacids which could compete for non-specific decarboxylases. The insoluble ODC activity appears largely within synaptosomal and mitochondrial-enriched morphological fractions, yet cannot be attributed to trapped soluble ODC. Particulate ODC has a pH optimum and kinetic parameters that differ from those of soluble cerebral ODC.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
For improved accessibility of PDF content, download the file to your device.
Current View