Experimental Studay Of Synthesis And Biodistribution Of ¹³¹Ⅰ-His-Indomethacin In Rats' Pulmonary Tumor Model.

ObjectiveTo studay the method of Indomethacin(IN) labeled by(131)~I.,one of the non-steroidal anti-inflammatory drugs has obviously anti-tumors effects.Futhmore to studay the chemical synthesis,preparation,quality control of(131)~I-His-IN.and to observe the(131)~I-His-IN biological distributions in rats bearing lewis pulmonary tumor.MehodsHis-IN was labeled with(131)~I by Ch-T method.Thin-layer chromatography(TLC) was performed using silicagel GF254 coated on glass plates,using Chloroform and methanol as the mobile phase.35 kunming rats were made into lewis pulmonary tumor model rats.35 rats were taken out randomly when the longest diameter of their tumors was 10mm,and were divided into 7 groups.Every rat was given 180KBq(0.2ml)(131)~I-His-Indomethacin(including (131)~I-His-Indomethacin 125μg).Collected the blood by taken eyeball at 2,4,8,12,16,24,48h after given the(131)~I-His-IN respectly.Then collected organs or tissues such as heart,liver, spleen,lung,kidney,stomach,thyroid gland,tumors and so on.,were counted for radioactivity and determined as%ID/g.The other 35 nude rats were dealed with as the instructions as above.ResultsThe structure of His-IN was confirmed through the mass-spectrum and hydrogen-spectrum. A kit developed with the synthetic His-IN and(131)~I,then added the chloramine-T(Ch-T) as an oxydant.His-IN was labled by adding,stired 1 min at room temperature.The average radiochemical yields is 52%.Through three extractions by acetic ether and distilled water, high radiochemical purity reached 95%.After 1,3,7days stored at room temperature,the radiochemical purity was 93.5%,90.2%and 89.2%respectively.The highst%ID/g of tumor tissue is 2.31±0.41 at 8h.High tumor/blood ratios (1.86±0.28 at 8h),tumor ratios(2.67±0.62 at 12h) and tumor ratios(2.45±0.32 at 16h). Furthermore,the ratios became higher with the time delayed.ConclusionThe method of His-IN labeled by(131)~I is feasible.(131)~I-His-IN could accumulated in tumors specificityly and the clearance is slowly than other organs or tissures obviously. (131)~I-His-IN may have better effect in tumor therapy.