Abstract
Object:An integrated toxicokinetic-toxicodynamic (TK-TD) modeling approach within a nonlinear mixed-effect modeling framework is applied to investigate concurrent abnormal heart rate and QT changes in SD rats,which were examined after the oral administration of processed Aconitum kusnezoffii(PAK).Aconitum kusnezoffii(AK),and compatibility of Terminalia chebula(AKCT) in Mongolian respectively,to elaborate scientifically and thoroughly the Synergism and Attenuation Effects of Terminalia chebula.Method:A part of SD rats received a single dose of CMC-Na (control) and PAK at0.36mg/kg via oral gavage on a day around8AM,respectively,and a dose-gradient of AK and AKCT at 0.36,0.42,0.49mg/kg.While,another part of rats received standard solution of Aconitine only injected into their tail vein.Blood samples were collected from cervical artery of rats at 0.5,1,1.5,2,3,5,7,10,12 and 24h after each dose.ECG data was collected by BL-420system.(1)The establishment of UPLC/Q Exactive MS assay to detecte Aconitine(AC),Hypaconitine(HA) and Mesaconitine(MA) in blood.by using Dionex UltiMate3000 fast ultra high performance liquid chromatography;Q Exactive quadrupole electrostatic field rail trap high resolution mass spectrometry system ;Hypersil GOLD .Qualitative screening and quantitative detection were carried out by the full scanning/selective ion monitoring model of high resolution mass spectrometry.(2)TK-TD modeling:Igeneralyl,according to the principle of AIC or the minimum square sum of the weighted residuals,the optimum atrioventricular model is chosen to obtain the toxicokinetic and toxicodynamic parameters of toxicant effect.A quantitative equation for the establishment of effects and concentration of blood drugs by mathematical methods with the help of ADAPT5 software(BMSR,USC).Result:(1) Mobile phase A 0.1% formic acid:mobile phase B acetonitrile=35:65,and flow rate is 0.2mL/min.Injection volume is 3uL.Collection quality range 600-700m/z and Ion detection (SIM):m/z646(AC),m/z 616(HC),m/z 632(MC).Linearity was proved by the analysis of ten spiked serum samples resulting in calibration curves (n=3) with correlation coefficients r=0.9999 for each diester AC.According to the ICH guidelines the limit of detection(LOD) of AC and HC was better in 600～10000 ng/mL,while MC was in 100～5000 ng/mL.The lower limit of quantitation (LLQ) of AC was5ng/mL,and HC and MC was0.5ng/mL,10ng/mL,respectively. The precision results of RSD are less than5%, and the precision of the method is in accordance with the requirements for the determination of biological sample content..
