Pipkin J L, Hinson W, Lyn-Cook L E, Duffy P H, Feuers R J, Leakey J E, Aly K B, Hart R W, Casciano D A
Division of Genetic Toxicology, National Center for Toxicological Research, AR 72079-9502, USA.
Aging (Milano). 1996 Aug;8(4):263-70. doi: 10.1007/BF03339577.
The labeling in vivo of young ad libitum (Y/AL) and old diet restricted (O/DR) rats with [3H]retinoic acid (RA) for 6 hours, and the exposure of electrophoretically separated nuclear matrix proteins from bone marrow tissue on film for 48 days revealed the presence of eleven retinoylated proteins. Dosing with RA (100 mg/kg body weight) for 96 hours and exposure to [3H]RA enhanced the levels of radioactive incorporation of several nuclear matrix proteins, including p51, and p55, similarly in Y/AL and O/DR rats. Dosing of old ad libitum (O/AL) rats with [3H]RA for 6 hours showed the incorporation of six proteins following 48 days of exposure on film. Long-term dosing of RA (96 hours) did not increase [3H]RA incorporation in these proteins, including p51 and p55, in O/AL rats. Increasing the level of RA by two-fold (200 mg/kg body weight) in Y/AL and O/DR rats elicited an increase in the incorporation levels of [3H]RA in five proteins. This dose response following increased levels of RA was not seen in the retinoylated proteins of O/AL animals. Analysis by the Western blotting technique showed p51 and p55 from rat bone marrow cells to have the same immunochemical determinates with proteins of identical molecular masses in HL60 cells. The levels of retinoylation of nuclear matrix proteins in O/DR animals, altered by age- and diet-dependent factors, suggests a condition that is more reminiscent of Y/AL than of O/AL animals.
用[3H]视黄酸（RA）对自由摄食的年轻（Y/AL）和饮食受限的老年（O/DR）大鼠进行6小时的体内标记，并将骨髓组织中经电泳分离的核基质蛋白在胶片上曝光48天，结果显示存在11种视黄酸化蛋白。用RA（100毫克/千克体重）给药96小时并暴露于[3H]RA后，Y/AL和O/DR大鼠中几种核基质蛋白（包括p51和p55）的放射性掺入水平均有所提高。对自由摄食的老年（O/AL）大鼠用[3H]RA给药6小时，在胶片上曝光48天后显示有6种蛋白发生掺入。在O/AL大鼠中，长期给予RA（96小时）并未增加这些蛋白（包括p51和p55）中的[3H]RA掺入。在Y/AL和O/DR大鼠中，将RA水平提高两倍（200毫克/千克体重）会使5种蛋白中的[3H]RA掺入水平增加。在O/AL动物的视黄酸化蛋白中未观察到RA水平升高后的这种剂量反应。蛋白质印迹技术分析表明，大鼠骨髓细胞中的p51和p55与HL60细胞中分子量相同的蛋白具有相同的免疫化学决定簇。O/DR动物中核基质蛋白的视黄酸化水平受年龄和饮食相关因素影响而改变，这表明其状况更类似于Y/AL动物而非O/AL动物。
