Age-related changes in neuronal uptake of catecholamines.

Age-related changes in the neuronal uptake of labelled noradrenaline were analyzed in transversally sectioned portions of 4-, 12- and 20-month old rat vas deferens. Uptake was a saturable process apparently following the Michaelis-Menten equation. By determining the values of Km and Vmax, it was possible to conclude that neuronal uptake does not change with age in the epididymal portion of the vas deferens and is reduced in the prostatic portion of 20-month old rats.