Substrain differences of age-related changes in in vivo dopamine synthesis in the striatum and nucleus accumbens of the rat brain.

The purpose of this study was to investigate age-related changes in in vivo dopamine (DA) synthesis in the brain of Wistar rats of ST and LWH substrains. There were no significant differences in the regional DA levels in aged versus mature rats of both substrains. In the LWH substrain, the in vivo DA synthesis as reflected in 3,4-dihydroxyphenylalanine accumulation in the striatum and nucleus accumbens was significantly lower in the aged rats. In the ST substrain, however, no age-related changes in the regional in vivo DA synthesis were observed for the mature rats. These results suggested that the striatum and nucleus accumbens of the LWH rats may be more vulnerable to aging than those of ST substrain.