老年大鼠与断奶大鼠脑细胞核染色质的非组蛋白研究

用不连续盘状SDS-聚丙烯酰胺凝胶电泳分析并比较了老年大鼠与断奶大鼠脑细胞核NHCP,也比较了二者的组蛋白与DNA、NHCP与组蛋白、NHCP与DNA之比值。发现老年大鼠NHCP含量明显减少;断奶大鼠的NHCP与DNA、NHCP与组蛋白之比值明显高于老年大鼠,而组蛋白与DNA之比值却近于1。从二者的NHCP电泳图谱可见,老年大鼠丢失了表观分子量10万以上的两条蛋白区带及表观分子量3万以下的一条蛋白区带;老年大鼠与断奶大鼠比较,表观分予量6—9万的蛋白区带杂色浅,而表观分子量4.3万的蛋白区带染色深。总之,老年大鼠脑细胞核NHCP发生质与量的变化。

INVESTIGATION OF THE RELATIONSHIP BETWEEN BRAIN CELL NONHISTONE CHROMATIN PROTEIN (NHCP) OF WEANING RATS AND AGING RATS

The relationship between brain all nonhistone chromatin protein (NHCP) of weaning rats and aging rats was investigated. Nuclei were prepared from Wistar rats of weaning and aging on sucrose gradient centrifuga-tion. NHCP, histone and DNA were extracted from the nuclei and quantitated by Lowry's method and diphe-nylamine reaction. It was found that NHCP decreased in aging rats and disc SDS-PAGE of NHCP showed electrophoresis heterogeneity in relation of age. Three NHCP bands (>100.000; <30,000 mol. wt.) are dep leted in aging rats, two regions (approx. 90,000, 60,000-70,000 mol. wt.) decreased in aging rats, and one regiem (approx. 43,000 mol. wt.) increased in aging rats. In general, NHCP of brain nucleus of aging rats was changed both in quantity and in quality.