Abstract
Chronic application of Piracetam decreases 3-methylcholanthrene-induced increased GABA content in the brains of rats and delays tumor appearance. The most active inhibitor of GABA-transaminase, amino oxyacetic acid (AOAA), increases the GABA content in the brain and appears to increase the tumor rate in 3-MC rats. Despite some reservations in view of results derived from investigations of only two compounds (3-MC and Piracetam) we suppose that a relation exists between effects on central nervous system and peripheral carcinogenesis. We will try to support our hypothesis further by using other compounds influencing the GABA-content of the brain.