A development of new radiopharmaceuticals for respiratory diseases

本文报道用<99m>锝气体发生器从锝气体中产生不同的示踪剂。在97%氩和3%氧的存在下，在发生器中产生过锝气体（P-gas）。P-gas在磷酸盐缓冲液（PBS）中的易提取性，静脉注射P-gas后在大鼠体内的分布和放射色谱分析结果表明，P-gas的性质类似于过锝酸盐（TcO_4^-）。<99m>Tc-DTPA气体（D-气体）也在相同条件下由technegas发生器产生。D-gas与P-gas在体外实验中表现出相同的理化特性，在体内实验中，吸入P-gas的清除半衰期（T_（1/2））与TcO_4 ~（2-）气雾剂无显著性差异，但P-gas的T_（1/2）明显快于DTPA气雾剂。吸烟者的P-气体T_（1/2）明显快于非吸烟者（P&lt;0.01），正常非吸烟者的D-气体T_（1/2）为19.8 ± <plus-minus>4.0min，<plus-minus>吸烟者为12.0 ± 2.8min，<plus-minus>特发性间质性肺炎（IIP）为31 ± 11.2min。

The aim of this study is to generate different tracers from ^<99m>Tc-technegas by using Technegas generator.Pertechnegas (P-gas) was formed in the generator in the presence of 97% Ar and 3% oxygen.The easy extractability of P-gas in the phosphate buffered saline (PBS), the distribution seen in rats after intravenous injection of P-gas and the results of the radiochromatography showed that P-gas behaved like pertechnetate (TcO_4^-).^<99m>Tc-DTPA gas (D-gas) was also generated in the same condition by technegas generator. D-gas showed same physicochemical sharacteristics to P-gas in vitro experiment.In vivo study, the clearance half time (T_<1/2>) of inhaled P-gas has shown no significant difference to that of TcO_4^- aerosol.T_<1/2> of P-gas was considerably faster in comparison with T_<1/2> of DTPA aerosol. However, T_<1/2> of P-gas was more rapid in smokers compared with T_<1/2> in nonsmokers (p<0.01).T_<1/2> of D-gas was 19.8<plus-minus>4.0 min in normal non-smoker subjects, 12.0<plus-minus>2.8 min in smoker subjects, and 31<plus-minus>11.2 min in idiopathic interstitial pneumonia (IIP)Further study of the clearance of these tracers in pulmonary diseases is required to assess clinical usefulness.