Studies On Pharmacokinetics Properties Of Traditinal Chinese Medicine Percutaneous Preparation In Plasma And Milk Of Cows

The traditional Chinese medicine percutaneous preparation had the effect of antisepticizing, antiphlogosis, promoting blood flow and removing blood stasis. It was used to treat the mastitis of cows and was made by the staff of veterinary pharmaco-teaching room in Northeast Agricultural University. The studies on its pharmacokinetics properties were carried out in order to explain its absorbed and metabolic process in cows.The reversed phase high-performance liquid chromatography (RP-HPLC) method was established in this experiment which was used to detect simultaneously the two effect ingredient (baicalin and forsythin) of the traditional Chinese medicine percutaneous preparation in milk and plasma of cows. Chromatographic condition was that chromatographic column was Kromasil C₁₈ (4.6×200mm,10μm); Mobile phase was methanol-0.002% phosphoric acid solution; Detecting wavelength was 280nm.The standard curves of baicalin and forsythin in milk were linear in range of 0.01～5.0μg·mL^-1, the coefficient of correlation (r) was 0.9977 and 0.9958 respectively.The average recovery of them was 90.39% and 88.02%, respectively. The average coefficient of variation of the bacalin during one day and five days were 1.81% and 1.82%, respectively; The average coefficient of variation of the forsythin during one day and five days were 2.69% and 3.87%, respectively. The standard curves of baicalin and forsythin in plasma were linear in range of 0.01～4.0μg·mL^-1, the coefficient of correlation were 0.9955 and 0.9973, respectively. The average recovery of them was 89.73% and 92.79%, respectively. The average coefficient of variation of the bacalin during one day and five days were 1.82% and 3.28%, respectively; The average coefficient of variation of the forsythin during one day and five days were 2.97% and 3.05%, respectively. The method can be used for the detection of biological specimen of pharmacokinetics research because of its good reproducibility; high precision; convenience and economics.The plasma and milk samples were collected at different time point after single percutaneous administration on the breast with disease of the 4 cows. The drug concentration data measuring by the established RP-HPLC were analyzed by MCPKP which was pharmacokinetics auto-analyzing program. The results indicated that baicalin and forsythin had not been detected in plasma after single percutaneous administration on the breast with disease. The results showed that the concentration-time courses of the bacailin and forsythin in the milk fit to a one-compartment open model with the first order absorption after single percutaneous administration on the breast with disease. The theory equation of baicalin in the milk was C=6.2024(e^0.2271t-e^0.3841t). The main pharmacokinetics parameters of baicalin in the milk were as following, T_max=4.9392h, C_max=2.8399μg·mL^-1, t_1/2ka=1.803h, AUC=27.32mg·L^-1·h^-1, lagtime=0.7467h, t_1/2k=3.0520h, K=0.2271·h^-1, T_CP=28.319h; The theory equation of forsythin in the milk was C=1.3942(e^0.3399t-e^0.3275t). The main pharmacokinetics parameters of baicalin in the milk were as following, T_max=3.6799h, C_max=0.4922μg·mL^-1, t_1/2ka=2.1158h, AUC=4.1015mg·L^-1·h^-1, lagtime=0.683h, t_1/2k=2.0386h, K=0.3399·h^-1, T_CP=14.525h..The two effect ingredient had the slow-release action after single percutaneous administration on the breast with disease. They absorbed slowly through the breast but the absorbed degree was high. They eliminated slowly, too.So the traditional Chinese medicine percutaneous preparation brought local action into full play. The baicalin and forsythin got into milk through diffusion because they were the low polarity substance. Because the toxicity of traditional Chinese medicine was relatively low and baicalin and forsythin had not the corroborant toxicity, it was suggested to plan the withdrawal time according to the associated applied antibiotics when the residual was considered.If the antibiotics was not used simultaneouly, the milk can be drink when it had not the physical and chemical changes.