| Popis: |
The literature concerning age effects on cholinergic neurochemical parameters, in the brain presents a heterogeneous picture, both within and among species. Whereas some studies of human postmortem material have demonstrated age-dependent declines in choline acetyltransferase (ChAT) activity in various brain regions (5, 12, 19), others have revealed no ChAT losses in some of the same regions (5, 10, 12, 19, 28). In brain regions from C57BL/6J and A/J mice, we have observed age-dependent increases in ChAT (26); whereas, other studies have revealed no changes or decreases in the brains of C57BL/6J mice (23, 25), other mouse strains (24), and rats (2, 23, 25). |
