Objective To prepare long-circulating temperature-sensitive liposomes with paclitaxel( LTSLP ),develop methods for determination of paclitaxel,related substances and monostearoyl phosphatidylcholine( MSPC ) in LTSLP,and the haemolysis of LTSLP in vitro. Methods HPLC-UV methods for paclitaxel content and related substances and HPLC-CAD method for MSPC in LTSLP were established and validated. Spectrophotometric method was used to determine hemolysis in vitro. Results There was a good linear relationship between peak area and concentration within the range of 60. 39-181. 17μg·mL-1 . Recovery and precision of the method for determination of paclitaxel content met the requirements. Specificity,sensitivity,and system suitability for related substances were consistent with requirements. There was a good linear relationship between peak area and concentration within the range of 1. 5-50. 0μg·mL-1 for the determination of MSPC with good specificity,sensitivity and recovery. Paclitaxel contents in three batches of self-prepared LTSLP were between 90. 0% and 110. 0%,single related substances were below 0. 5% and total impurities were below 2. 0%. There was almost no hemolysis in vitro. Conclusion The methods for determining paclitaxel content,related substances and haemolysis can be used to assess the quality of LTSLP. Self-produced LTSLP consistently meet the quality standards.

Aim To study the effect of melatonin on expression and activity of myosin light chain kinase in the artery wall of atherosclerotic rabbits.Methods The rabbit model of atherosclerosis was induced by a high-cholesterol diet.The blood lipid levels were assayed in the serum of each group.MLCK expression was detected by Western blot and immunohistochemical method.MLCK activity was measured by ?-32P-ATP incorporation into myosin light chain.Results The atherosclerosis model was established successfully.The levels of lipids decreased after MLT treatment.After fed with cholesterol for twelve weeks,the expression and activity of MLCK in the artery of atherosclerotic rabbits increased markedly,whereas there was no obvious difference in expression of MLCK in the artery of atherosclerotic rabbits fed with cholesterol and melatonin for twelve weeks compared with that of control.Conclusions It was suggest that high expression and activity of MLCK in the artery might be closely correlated with the development of atherosclerosis.Melatonin played an important role in inhibiting the development of atherosclerosis by decreasing the expression and activity of MLCK.