[Autoradiographic studies on the distribution of 14C-piracetam in the simian brain]

Autoradiography of the brain of the monkey Callithrix jacchus 2 and 6 h after oral application of 200 mg 14C-piracetam/kg (2-oxo-pyrrolidine-l-acetamide-2-14C) shows that the drug is preferably concentrated in the cortex of cerebrum and cerebellum. This specific affinity of piracetam which was observed earlier in dog and rat is thus confirmed in the primate and seems to be species independent. Beside the dominant cortical concentration there is a characteristic storage of piracetam in many nuclei of other brain areas, for instance, nucleus caudatus, hippocampus, n. anteriores thalami, n. dorsales thalami, corpus geniculatum laterale and mediale, corpora mamillaria, nucleus supraopticus, substantia grisea centralis, colliculi superiores and inferiores. Furthermore piracetam is stored in the blood vessel wall of the brain over 6 h. The hypophysis and pineal body take up radioactivity intensively.