口服纳米银对大鼠的生物有效性及其体内分布的研究

摘要

Due to the unique antimicrobial properties,nanosilver (AgNP) are widely applied in many fields.However,its bioavailability,tissue distribution and excretion in rats are less known.Female Sprague-Dawley rats were treated by a single intragastic administration of 10 mg·kg-1 polyvinylpyrrolidone-AgNPs,and rat tissues,feces and urine were collected periodically to analyze total Ag concentrations by ICP-MS.The results showed that after uptake by gastrointestine,AgNP was transported via the blood circulation and distributed to tissues such as liver,kidney,spleen,lung,and brain.At 1 h after AgNP exposure,total silver accumulation in those tissues peaked (i.e.0.29 ± 0.13 mg·kg-1,0.23 ± 0.04 mg·kg-1,0.17 ± 0.05 mg·kg-1,0.11 ± 0.01 mg·kg-1 and 0.06 ± 0.02 mg·kg-1 for liv er,kidney,spleen,lung and brain,respectively),and declined to background levels over time.Our calculation showed that the bioavailability of AgNP to Sprague-Dawley rats via intragastric administration was 8.5％.Especially,73％ of the dosed AgNP was excreted via feces.%由于独特的抗菌特性,纳米银(AgNP)在诸多领域得到广泛应用,但是其生物有效性、动物组织分布及排出尚不清楚.将聚乙烯吡咯烷酮包被的AgNP溶液按照10 mg·kg-1给雌性SD大鼠灌胃,采用ICP-MS检测SD大鼠组织、粪便及尿液中总银浓度.结果表明,AgNP通过小肠吸收后,可以通过血液循环快速分布在肝、肾、脾、肺、脑等靶器官.灌胃后1h,大鼠各组织中总银浓度达到最大值(肝、肾、脾、肺、脑中银浓度分别为(0.29±0.13) mg·kg-1、(0.23±0.04) mg· kg-1、(0.17±0.05) mg· kg-1、(0.11±0.01) mg·kg-1、(0.06 ±0.02) mg·kg-1),之后银浓度随时间而降低,直至和对照组无显著性差异.在灌胃途径下,AgNP对SD大鼠的有效性为8.5％,且73％的AgNP是通过粪便的途径排出体外.