Partial restoration of choline acetyltransferase activities in aging and AF64A-lesioned rat brains by vitamin E

Abstract

It has been suggested that the activity of the enzyme responsible for the synthesis of acetylcholine, choline acetyltransferase (ChAT), is substantially reduced in the neocortex and hippocampus of Alzheimer's and other aging brains. d-α-Tocopherol (vitamin E), a free radical scavenger fat-soluble vitamin, was utilized in the present study to determine whether its supplementation in aging and ethylcholine mustard aziridinium (AF64A)-lesioned rats would improve the cholinergic hypofunction. Vitamin E (given 24 h and 15 min prior to AF64A administration) significantly (P < 0.01) reversed the effect of AF64A in hippocampal choline acetyltransferase activity, but it did not cause any change of this enzyme activity in other brain regions (striatum and frontal cortex), nor did it cause any significant change after 30-day daily treatment in AF64A-lesioned rats. Furthermore, vitamin E (50 mg/kg, i.p. for 30-day treatment) significantly (P < 0.01) partially restored the enzyme activity in striatum of aging (20-28 month old) rats. The present result indicates that vitamin E can partly restore the hypofunction of the cholinergic system in aging and partly prevent the toxicity in AF64A-lesioned rats. © 1993.