Carnitine acetyltransferase activity is not changed with age in rat brain and human platelets

Carnitine acetyltransferase activity was studied in different brain regions of the rat and in human platelets. The values of Km for carnitine and for acetyl-CoenzymeA (acetyl-CoA) were similar in cortex, hippocampus and striatum of the rat and in human platelets, suggesting that carnitine acetyltransferase might be a useful peripheral marker of its central activity. The activity of this enzyme was similar in the cortex and hippocampus of young and old rats. Furthermore, the determination of carnitine acetyltransferase activity in platelets from healthy volunteers showed no significant difference with age.