A sensitive and selective method based on gas chromatography hyphenated to mass spectrometry (GC-MS) was developed and validated for the determination of atractylon in rat plasma. Plasma samples were processed by liquid-liquid extraction with ethyl acetate-n-hexane (1:1, v/v) using acetophenone as an internal standard (IS). Analytes were determined in selective ion monitoring (SIM) mode using target ions at m/z 108.1 for atractylon and m/z 105.1 for acetophenone. The calibration curve was linear over the concentration range of 10-1000 ng/mL with lower limit of quantification of 10 ng/mL. The intra- and inter-day precision variations were not more than 10.4% and 9.6%, respectively, whilst accuracy values ranged from -6.5% to 4.9%. Extraction recovery of the assay was satisfactory. This method was suc-cessfully applied to quantification and pharmacokinetic study of atractylon in rat plasma after in-tragastric administration of Atractylodis extract.

Objective:To investigate the expression of aromatase of renal tissue in systemic lupus erythematosus(SLE)model mice.Methods:BALB/c mice were induced SLE with homologuous splenic cell activated with ConA after being ovariectomized,and in the same time administered different doses of benzestrofol.E2 in peripheral blood and renal tissue was detected by ELISA and the expression of mRNA of aromatase in renal tissue was detected by RT-PCR in the 4th,6th,8th and 10th weeks.Results:The level of E2 of peripheral blood and renal tissue of SLE model mice became higher as benzestrofol exogenously administered heightened.Compared with control mice,the level of E2 in SLE model mice increased,and the expression of mRNA of aromatase of renal tissue increased with E2 increment.Conclusion:E2 promotes development of SLE through regulating expression of aromatase mRNA.