AGE-RELATED DECREASE OF NERVE GROWTH FACTOR-LIKE IMMUNOREACTIVITY IN THE BASAL FOREBRAIN OF SENESCENCE-ACCELERATED MICE

The senescence-accelerated mouse P10 (SAMP10) is a murine model of acc elerated senescence characterized by the deterioration of learning and memory with advancing age. In the present study, we examined the dist ribution of nerve growth factor (NGF) immunohistochemically in SAMP10 mice and its control strain, SAMR1. In both strains, NGF-like immunore activity (NGF-IR) was observed in neurons throughout the entire forebr ain and in glial cells in a particular location. In aged SAMP10 mice, each layer of the cerebral cortex retained its NGF-IR, although the th ickness of the cortical mantle was markedly decreased in comparison wi th younger animals. There was an age-related decline in NGF-IR in the substantia innominata of SAMP10 mice at the age of 10 months, when com pared to 2-month-old SAMP10. These results indicate age-related decrea se of NGF in the basal forebrain in SAMP10 mice.