Effects of piracetam on the incorporation of 32P into the phospholipids of neurons and glial cells isolated from rabbit cerebral cortex.

In the search for the biochemical basis of the action of Piracetam, the effects of this encephalotropic substance on the neuronal and glial phospholipid metabolism was investigated. Piracetam increases the incorporation of 32P into phosphatidylinositol and phosphatidyl choline of both glia and neuronal cell bodies (Figs. 1 and 2). When taking the important role of phosphatidylinositol in the processes of synaptic transmission and axonal conduction into consideration, the data obtained in the present work suggest that piracetam may stimulate excitatory neurons and may be involved in the process of synaptic transmission. The stimulatory effect of piracetam on the incorporation of 32P into phosphatidylinositol and phosphatidyl choline appears to be mediated by noerpinephrine or another neurotransmitter. Glial cells, isolated from the cerebral cortex of a rabbit, contained approximately one-third more phospholipids per uint protein than the neuronal cell bodies. The distribution and pattern of phospholipid relative to the total amount, was rather similar in both cell types. The incorporation of 32P into phosphatidylinositol and phosphatidyl choline was somewhat faster in neurons than in glial cells. Compared to glial cells the neuronal cell fraction had a higher phospholipid turnover.