Biochemical localization of gamma-glutamyl transpeptidase within cellular elements of the rat cerebral cortex.

The presence of the enzyme gamma-glutamyl transpeptidase was established in cellular elements of the rat cerebral cortex. Lowest enzyme activity was found in the total cerebral homogenate while approximately four-fold increased enzymatic activities were evident in capillary-enriched, glial-enriched and purified neuronal fractions.