Abstract:Objective:To develop a HPLC method for the determination of tissue distribution of cinnarizine in rats. Methods: Cinnarizine (2 mg/Kg) was injected into the tail vein of rats. Tissue sample was alkalized with sodium hydroxide solution and extracted with methyl tert-butyl ether. The separation was performed on a Hypersil C18 column using methanol-water-glacial acetic acidacid-triethylamine (70300.60.4) as the mobile phase at UV 254 nm. The distribution of cinnarizine in the heart, liver, spleen, lung, kidney, stomach, small intestine, brain, fat and testes was determined. Results: The limit of detection of cinnarizine in the hepatic tissue was 0.02 μg /ml and the linear range was 0.05-1 0 μg/ml. The limit of detection in the intestine tissue was 0.02μg /ml and the linear range was 0.05-1 μg/ml, which meets the requirement for the analysis of biological samples. Cinnarizine was extensively distributed in rat body, with highest concentration found in the lung. Conclusion: Our method is easy to perform, accurate and sensitive, which makes it suitable for preclinical pharmacokinetic research of cinnarizine.