全反式维甲酸对大鼠棕色脂肪线粒体上解偶联蛋白活性和含量的影响

Effects of tRA on activity and content of uncoupling protein in rat brown adipose tissue mitochondria

目的 :探讨全反式维甲酸 (t RA )对大鼠棕色脂肪组织线粒体上解偶联蛋白 (UCP)活性和含量的影响。方法 :将大鼠分为 t RA组和对照组 ,用 3H标记的鸟嘌呤核苷酸 (3H- GTP)与线粒体上解偶联蛋白相结合 ,用液体闪烁仪测定其放射性活性 ,经 Scatchard Plot测定出两者结合的解离常数 (Kd)和最大结合量 (Bmax)。 结果 :t RA组 Bmax比对照组增加 1.48倍 ,Kd 值两组无明显差别 ,t RA组大鼠体重下降 ,棕色脂肪体积变小 ,白色脂肪变成淡红色。 结论 :t RA能使棕色脂肪组织线粒体中U CP含量增加 ,但不改变其活性 ;能增加棕色脂肪组织中脂肪消耗 ,可能在白色脂肪组织中诱导产生 UCP。

Objective: To evaluate effects of tRA on activity and content of UCP in rat brown adipose tissue mitochondria. Methods: The rats were divided into tRA treatment and control groups using 3H GTP binded UCP in mitochondria. Radioactivity was measured by liquid aglimmer instrument,the dissociation constant( K d)and maximal binding( B max )was determined from Scathard plot. Results: In tRA treatment rat, B max increased by 1.48 fold, K d remained unchanged, rat body weight loss and brown fat weight decreased, white fat became rosiness. Conclusion: tRA can increase concentration of UCP in brown adipose tissue mitochondria, but do not change its activity,it also can increase fat consumption,produce UCP from white adipose tissue. [