RESUMEN
AIM: To study the pharmacokinetics of bromotetrandrine (W198) in rats and beagle dogs. METHODS: The concentrations of W198 in serum were determined using HPLC method with UV detection. RESULTS: The pharmacokinetic parameters of W198 after single iv doses of W198 10, 20 and 40 mg x kg(-1) in rats were as follows: T1/2beta were 6.60, 7.36 and 6.77 h, AUC0-24 h were 3.797, 7.371 and 15.192 mg x h x L(-1), Vd were 7.14, 4.33 and 4.13 L x kg(-1), CL were 2.83, 2.60 and 2.71 L x (kg x h)(-1), respectively. The T1/2beta and AUCo-24 h of W198 after single im dose of W198 20 mg x kg(-1) in rats were 11.61 h and 12.646 mg x h x L(-1). The im bioavailability of W198 in rats was 56.9%. The T1/2beta, AUC0-24 h, Vd and CL of W198 after single iv dose of W198 5 mg x kg(-1) in beagle dogs were 11.72 h, 12.646 mg x h x L(-1), 0.70 L x kg(-1) and 0.46 L x (kg x h)(-1), respectively. The plasma protein binding ratio of W198 with human serum protein was 78.0%. CONCLUSION: The absorption of W198 in rats was of first order kinetics.