氚标记喹赛多在鸡体内处置的研究

Disposition of tritium-labeled cyadox in chicken

通过放射性标记示踪方法研究喹赛多(cyadox,CYX)在鸡体内的处置过程,探讨喹赛多的药理学与毒理学特性,为其合理用药和食品安全评价提供理论依据。在物料平衡研究中,一组6羽鸡一次性灌服[~3H]-CYX,每24 h收集粪便检测其放射性。在组织分布消除研究中,5组20羽鸡连续灌服[~3H]-CYX 7 d,不同时间点宰杀一组,检测各组织器官中的放射性。结果显示,鸡体内喹赛多的排泄速率快且较为彻底。粪便中排出的放射性药物占总给药剂量的95.94%,总回收率达到96.02%,未回收3.98%。连续灌服7 d后,喹赛多在鸡组织中分布广泛,停药后第6小时所检测的所有组织中都能检测到一定量的放射性,肝和肾中残留时间最长,但消除迅速。停药后第7天,大部分组织器官中的放射性均低于检测限。在鸡体内,停药后第6小时放射性总残留质量分数低于安全质量分数。喹赛多在鸡体内处置的研究表明,喹赛多在鸡体内吸收快,分布广泛,消除迅速,排泄较为彻底。

The disposition of cyadox （CYX） was investigated in chicken for its pharmacology,toxicology and food safety concerns.For the excretion studies,a group of 6 chickens were administered a single oral dose of tritium labeled CYX（[-3H]-CYX）,and feces were collected every 24 h from intact animals after the dose for 4 d.For the total depletion studies,20 chickens were divided into 5 groups.Each group consisted of 4 chickens,administered [-3H]-CYX for 7 consecutive days.One group of two male and two female chickens were randomly selected to be slaughtered at each time point （6 h,1 d,3 d,7 d,14 d） after withdrawal period.In result,excretion of radioactivity was rapid and nearly complete within 96 h after dosing.Total mean recovery of the radioactivity was 96.02% and radioactivity of excreted from feces were 95.94%.Radioactivity was observed in nearly all of the tissues in the first 6 h after 7 days of consecutive oral dosing.The highest radioactivity and longest persistencewere in the liver and kidney,where the majority of the radioactivity was cleared within 7 days.After 6 h,concentration of total radioactivity residues was lower than safe concentration in chicken.In conclusion,excretion of CYX was rapid and nearly complete after single oral dosing and tissue distribution of CYX was extensive after administered [-3H]-CYX for 7 consecutive days in chicken.