肺通气显像剂锝气体药代动力学研究

A study on Technegas pharmacokinetics in normal volunteers

目的研究锝气体(Technegas)在健康志愿者体内的分布及药代动力学特点。方法8名健康志愿者,单次吸入 Technegas(46.71±19.02)MBq 后,采用连续显像方法估算1,30 min 及1,2,4,6,8,10,12和24 h 全身和各器官的放射性,并将原始数据转换为百分吸入剂量率(%ID)。测量给药后1,10,20,30,40,50,60,75,90 min 和2,4,8,12,24 h 血清及2,4,6,8,10,12,24 h 尿样中的放射性,分别绘制血清时间-放射性曲线和尿时间-放射性曲线。应用纸层析法分析血清、尿样中放射性成分。结果吸入 Technegas 1 min 约90.29%ID 沉积在肺内,其次为胃、肝、肾、唾液腺和甲状腺等。24 h 肺内残留的 Technegas 为吸入量的(81.44±3.52)%。吸入 Technegas 1 min 后血样中即出现放射性,并在10～20 min 达到高峰,为(2.39±1.10)MBq/L。24 h 累积经肾排出放射性为吸入量的(18.75±6.62)%。纸层析结果提示血清中含有 Technegas 和^(99)Tc^mO_4^- 2种成分,尿中仅含有^(99)Tc^mO_4^-。结论 Technegas 吸入后主要沉积在肺部,并可以通过肺气-血屏障进入血循环。

Objective In the study, the pharmacokinetics and biodistribution of Technegas was investigated in 8 healthy volunteers. Methods A single dose of Technegas （46.71 ± 19.02） MBq was administered through inhalation. Whole body scintigraphy was acquired. The radioactivity over the critical organs and tissues were determined via ROIs at 1,30 min and 1,2, 4, 6, 8, 10, 12, 24 h after the inhalation. Blood samples were drawn at 1, 10, 20, 30, 40, 50, 60, 75, 90 rain and2, 4, 8, 12, 24 h, and urine samples were collected at 2, 4, 6, 8, 10, 12 and 24 h. Paper chromatography （PC） was undertaken to analyze the metabolite of Technegas. Results Gamma camera images showed that 90.29 % ID of the inhaled Technegas deposited in the lungs. Substantial radioactivity was also observed in stomach, liver, kidneys, salivary glands and thyroid. （81.44 ± 3.52） % of inhaled Technegas remained in the lungs at 24 h. Radioactivity was detected in blood as early as 1 min after inhalation, reaching the maximum of （2.39 ± 1.10） MBq/L at 10 to 20 min. A （18.75 ±6.62）% of radioactivity appeared in the urine within 24 h after inhalation. PC showed that there were two major metabolites in blood： oxidized ^99Tc^m and particle bound ^99Tc^m. In urine, there was mainly oxidized ^99Tc^m. Conclusion Following inhalation, substantial ^99Tc^m carbon particles could pass into the systemic circulation.