Pharmacokinetics of m-nisoldipine Controlled-release Pellets in Beagle Dogs

OBJECTIVE To establish a method of HPLC-MS for studying the pharmacokinetics of m-nisoldipine controlled- release pellets after a single oral administrations in Beagle dogs. METHODS To determine the plasma concentrations of m-nisoldipine controlled-release pellets and conventional pellets after a single oral administration in Beagle dogs by HPLC-MS. The pharmacokinetic parameters were calculated by DAS 2.0 software. RESULTS The pharmacokinetic parameters for the single oral administration of controlled-release pellets and conventional pellets were t_max(11.154±0.5077)h and(2.213±0.3225)h, C_max(79.40±10.60)ng·mL^-1 and (116.7±20.35)ng·mL^-1, AUC(1227.8±296.0)ng·h·mL^-1 and (867.8±146.7)ng·h·mL^-1, respectively. The relative bioavailability of controlled-release pellets was 141.5%. CONCLUSION The method of HPLC-MS is accurate and sensitive. The plasma concentration of m-nisoldipine controlled-release pellets is steady and the effective plasma drug concentration can be maintained for a longer time.