【摘要】 目的:建立稳定同位素L1-5N亮氨酸测定大鼠骨骼肌蛋白质合成率的方法。方法:分别测定静脉注射相同剂量L1-5N亮氨酸不同时相的大鼠骨骼肌15N丰度及不同剂量L1-5N亮氨酸同一时相的大鼠骨骼肌15N丰度。结果:大鼠骨骼肌游离氨基酸池中15N同位素丰度在注射后30 m in内呈线性上升并达高峰,维持4 h后缓慢下降,骨骼肌蛋白质中的15N丰度30 m in至12 h基本维持不变;随着注射剂量的增加,大鼠骨骼肌蛋白质分数合成率亦增加,当L1-5N亮氨酸剂量>1.0 mmol/kg,分数合成率并不随施加L1-5N亮氨酸剂量的加大而增加。结论:在进行大鼠骨骼肌蛋白质合成率测定时,一次性静脉注射的测量最佳时限为30 m in,剂量为1.0 mmol/kg。更多还原

【Abstract】 Objective: To develop a new technique for measuring synthesis rates of skeletal muscle protein in rats with L-¹⁵N Leucine.Methods: After the intravenous injection with L-¹⁵N Leucine,the enrichment of ¹⁵N was measured in different time intervals with the same dosage and at the same time by variable dosage.Results: During the period from 0 to 30 minutes,there was nearly a linear increase of the enrichment of ¹⁵N of free amino-acid pool in rats′ skeletal muscle.The level of enrichment of ¹⁵N was kept to be plateau between 0.5 and 12 hours.And with the increase of dosage,FSR was rising.When the dosage was more than 1.0 mmol/kg,there was no significant discrepancy. Conclusion: For measuring synthesis rates of skeletal muslce protein in rats,sampling 30 minutes after injection is optimal and the most suitable dosage of L-¹⁵N Leucine is 1.0 mmol/kg.更多还原