同位素标记示踪法测定G蛋白竞争性抑制肽-27在动物体内的分布与排泄

Isotope tracer labelling method for determination of distribution and excretion of GCIP-27

目的:利用同位素标记示踪法研究G蛋白竞争性抑制肽(GCIP)-27在动物体内的分布和排泄。方法:125I-GCIP采用Iodogen法标记,按组织器官直接测定法和TCA沉淀法进行体内分布实验,以每毫克组织器官的125I-GCIP放射性计数表示GCIP在小鼠体内的分布;以不同时间段大鼠胆汁、尿、粪及小鼠的尿、粪放射性总排泄量占给药量放射性的百分比表示其在体内的排泄。结果:GCIP-27在小鼠体内分布广泛,其中肾、血管、胃、肺、心、小肠等组织分布较高,肌肉、脂肪等组织相对较低,脑最低。大鼠72h粪、尿、胆汁原形药物排泄量分别为给药量的26.13%,0.95%和4.12%。小鼠72h粪、尿原形药物排泄量分别为给药量的27.92%,0.84%。结论:GCIP-27在小鼠体内广泛分布,主要经尿液排泄,肾为主要排泄器官。

OBJECTIVE To study the distribution and excretion of GCIP-27 （G protein inhibitory polypeptide-27） in anirnals.METHODS ^125I-GCIP-27 was prepared by Iodogen method, the distribution and excretion were measured by direct assay and trichloroacetic acid （TCA） precipitation method after iv ^125I-GCIP. RESULTS GCIP-27 was shown to be widely distributed to the various tissues. There was a relatively higher in kidney, blood vessel, stomach, lung, heart, mall intestine and so on, and relatively lower in fat and muscle,and the lowest in brain. GCIP-27 excreted in urine,feces and bile within 72 h was 26. 13%,0. 95% and 4. 12% in rats respectively,and urine,feces within 72 h was 27. 92% ,0. 84% in mice respectively. CONCLUSION The distribution of GCIP-27 is extensive and the parent compound was mainly excreted by urine,and,kidney is main emunctory.