Sodium dependent uptake of 3H-choline in the cerebral cortex of ageing male rats.

Uptake of 3H-choline and the binding of 3H-hemicholinium-3 in the cerebral cortex was investigated in male Wistar rats of different ages. The effect of Al3+-ions on 3H-choline uptake was also studied. Na-dependent high affinity uptake of 3H-choline and 3H-hemicholinium binding were lower in 10- to 11-month-old rats than in 3- to 4-month-old rats. There was no further decline in these parameters from 10- to 11-month-old to 24- to 25-month-old rats. Al3+-ions had no effect on the uptake of 3H-choline. The present study supports the hypothesis that there is a relationship between Na-dependent high affinity uptake of 3H-choline and the binding of 3H-hemicholinium in the crude synaptosomal fraction of the rat cerebral cortex.