Study On Effect Of Chinese Herb Platycodon Grandiflorum On Pharmacokinetics Of Levofloxacin And Distribution In Tissues In Chickens After Oral Administration

Objective: To study the effect of Chinese herb Platycodon grandiflorum on pharmacokinetics of levofloxacin in chickens and distribution in tissues after oral administration.Methods: 72 healthy chickens were allocated into two groups of 36 chickens each at random. The chickens in group Ⅰ were orally given with single dose of Levofloxacin at 10mg/kg· b ·w ,The chickens in group Ⅱ were orally given with single dose of Levofloxacin at 10mg/kg·b·w and platycodon grandiflorum at 2g/kg· b ·w simultaneously. The concentrations of Levofloxacin in plasma and tissues(included heart,lung,liver,kidney) were determined by high performance liquid chromatography with a limit of detection of 0.001mg /L in plasma and 0.001μg/g in tissues, respectively. The pharmacokinetic variables were calculated by 3P97 PK program.Results:The Model were fitted a two-compartment Model with 1st Order Absorption(weight=1).The main pharmacokinetics parameters and calculated-equations in chickens were as follows, respectively: Group Ⅰ : T_1/2Ka=0.815±0.043h,T_1/2α=1.267±0.029h, T_1/2β=3.492±0.352h, T_peak=1.624±0.073h, C_max=1.715±0.l06mg/L, AUC=9.470±0.690 (mg/L·h), Ka=0.852±0.046 (1/h), MRT_{0→36(h)}=4.759±0.017h, C=6.893·e^-0.547t+1.322· e^-0.2toGroup Ⅱ :T_1/2Ka=1.027±0.137h, T_1/2α=1.696±0.383h, T_1/2β=9.238±1.170h, T_peak=2.034 ±0.020h, C_max=1.631±0.022mg/L, AUC=13.025±0.301(mg/L·h), Ka=0.684±0.099 (1/h), MRT_{0→36(h)}=7.154±0.084h, C=9.653·e^0.421t+0.521· e^0.076t. Conclusions:(1)Levofloxacin in healthy chickens was quickly absorbed with high concentration in plasma, distributed widespread, and eliminated slowly. (2)Platycodon grandiflorum could influence the pharmacokinetic variables of Levofloxacin in healthy chickens significantly: decreased the speed of absorption, but enhanced the degree of absorption ; accelerated the distribution from blood to tissues ; retarded the speed of elimination, increased the time of drug action.(3)Platycodon grandiflorum Leading action could influence notably the distribution of Levofloxacin in healthy chickens: increased the drug concentration of lung tissue , increased the concentration of heart tissue, increased the drug concentration of kindey tissue, but decreased the drug concentration of liver.