Biochemical studies on brains of young and old inbred (BC3F1) mice

Brains of 9 BC3F1 mice, 5 aged 6 months (young group) and 4 aged 29 months (old group), were studied. Basic protein (BP) content as determined by radioimmunoassay was significantly (0.05 less than p less than 0.02) increased in the old mouse group with a mean value of 6.2 mg BP/g dry weight as compared to the young group wiith a mean value of 4.6 mg BP/g dry weight. Phenol-formic acid-water disc gel electrophoresis of whole brain homogenates showed increased density of the basic protein low-molecular-weight component in the aged mouse as compared to the young. Water content, total protein content and 2',3'-cyclic nucleotide 3'-phosphodiesterase specific activity were unchanged with increasing age.