稳定性核素在测定大鼠组织蛋白质合成中的应用  

Measuring the tissues′ protein fractional synthesis rates with stable isotope in rats

作　　者：周济宏[1] 李幼生[2] 姜会庆[1] 曹亚澄[3] 韩勇[3] 黎介寿[2] 

机构地区：[1]南京军区南京总医院烧伤整形科,江苏南京210002 [2]南京军区南京总医院解放军普通外科研究所,江苏南京210002 [3]中国科学院土壤研究所,江苏南京210008

出　　处：《肠外与肠内营养》2006年第6期342-345,349,共5页Parenteral & Enteral Nutrition

基　　金：国家自然科学基金资助项目(批准号:30271263)

摘　　要：目的:研究应用稳定性核素(L-15N亮氨酸)测定大鼠组织蛋白质合成率的方法。方法:分别测定静脉注射相同剂量L-15N亮氨酸不同时相的大鼠组织15N丰度及不同剂量L-15N亮氨酸的同一时相大鼠组织15N丰度。结果:大鼠组织中游离及结合氨基酸同位素丰度在注射后半小时内几乎呈线性上升并达高峰,游离氨基酸15N丰度维持4h后缓慢下降,结合氨基酸15N丰度在半小时至12h之内基本维持不变;随着注射剂量的增加,大鼠组织蛋白质分数合成率亦增加。当L-15N亮氨酸剂量>1.0mmol/kg,分数合成率并不随施加L-15NLeucine剂量的加大而增加。结论:在进行大鼠组织蛋白质合成率测定时,一次性静脉注射的测量最佳时限为半小时,剂量为1.0mmol/kg。Objective：To develop a new technique for measuring synthesis rates of tissues＇protein in rats with L-^15N Leucine. Methods：After the intravenous injection with L-^15N Leucine,the enrichment of ^15N in different time intervals was measured with the same dosage and at the same time by variable dosage. Results ： Duing the period from 0 to 30 minutes, there was nearly a linear increase in enrichment of 15 N of free amino-acid pool in rats＇tissues, and the peak was achieved. For bond amino-acid pool, the level of enrichment of ^15N was in the plateau between 0.5 and 12 hours. With the increase of dosage, FSR was rising. When the dosage was more than 1.0 mmoL/kg, there was no significant discrepancy. Conclusions ：For measuring synthesis rates of tissues＇protein in rats, 30 minutes after the injection is optimal and the most suitable dosage of L-^15N Leucine is 1.0 mmol/kg.

关 键 词：稳定性核素 L-^15N亮氨酸 蛋白质合成率 分数合成率 

分 类 号：Q591.2-33[生物学—生物化学]