Changes in catecholamine levels in discrete regions of rat brain during aging.

The effect of aging on the levels of dopamine (DA) in striatum and noradrenaline (NA) in cerebral cortex, cerebellum, hypothalamus, midbrain and pons-medulla from young adult and five groups of aging rats was evaluated. Determinations of the levels of these amines were conducted. Age-related changes which commenced at 12 months were observed in specific brain regions. The endogenous content of NA decreased significantly in hypothalamus, midbrain, and pons-medulla when compared with the same regions from young adult animals. These results show that central noradrenergic system is markedly vulnerable to the aging process in rats.