In the old rat, the gray value of AChE-P neurons of the globus pallidus is notably higher than that in the young rat, but the value of nearly 6.8% of the positive cells in 24-month-old rat is inferior to the average value in 3-month-old rat (117.8).

• 老龄苍白球AChE-P神经元的灰度值；明显高于幼龄组；但约有6.；8%25老龄阳性神经元的灰度值低于幼龄的平均灰度值(117