The effects of aging on brain dopamine transporters was evaluated in 2
6 healthy male volunteers (age range, 21-63 years) using positron emis
sion tomography and [C-11]cocaine. The ratio of the distribution volum
e for [C-11]cocaine in basal ganglia to that in cerebellum was used as
a model parameter for dopamine transporter availability and showed a
significant negative correlation with age (r = 0.65, p < 0.0005). This
results document an age-related decline in dopamine transporters in h
ealthy individuals.