In order to observe and compare the neuron density and S100 expression in strata griseum of the SC of young adult and old cats,and to explore the causation and significance of age-related changes.

• 为观察、比较青年猫和老年猫上丘(superior colliculus SC)灰质层神经元密度及S100蛋白表达的变化；探讨导致相关变化的原因及其意义.