抄録
Studies were made on the effects of in vivo administration of an "antidementia drug", pantoyl-GABA, on choline acetyltransferase (ChAT) activity in mouse brain. Male ICR mice were treated intraperitoneally with 500 mg/kg of pantoyl-GABA, once a day, for various periods. Then they were killed, and the ChAT activities of their cerebral cortex, hippocampus and striatum were measured. Results showed that ChAT activity increased significantly in the cerebral cortex and hippocampus from day 5 and 7, respectively, of treatment, but did not increase in the striatum even after treatment for 14 days. The kinetics of ChAT activity were investigated in tissues from the cerebral cortex and hippocampus of mice treated with the drug for 7 days. Drug-treatment increased the Vmax value, but did not affect the Km values for choline and acetyl-CoA. These results indicate that longterm treatment with pantoyl-GABA enhanced ChAT activity, without altering the affinity of the enzyme for either substrate.