目的：建立鼠尾草酸灌胃给药后大鼠胃肠组织中鼠尾草酸含量的高效液相色谱测定方法，考察鼠尾草酸灌胃给药后在大鼠胃肠组织中的分布情况。方法：大鼠灌胃给予鼠尾草酸混悬液(90 mg·kg-1)后，于不同时间点将大鼠断头处死，采集胃肠组织，经过生物样品预处理后，采用HPLC UV测定不同时间点大鼠胃肠组织中的药物浓度。结果：鼠尾草酸的质量浓度在标准曲线范围内呈现良好的线性(r>0999)，线性范围为0321 2～1606 mg·L-1。组织样品的回收率，日内和日间精密度及准确度，稳定性均符合生物样品分析的相关要求。鼠尾草酸组织分布的研究结果表明，胃壁上的分布较多，随着时间的延长浓度逐步降低，最高为(3071±1192) μg·g-1；而在肠壁上的分布较低，随着时间的延长，经历了先升高后降低的过程，在给药后1 h浓度达到最高(3332±1770) μg·g-1。结论：首次建立了胃肠组织中鼠尾草酸浓度的高效液相色谱测定方法，该方法简便、快速，结果准确、可靠，并且首次阐明了灌胃给药后鼠尾草酸在胃肠组织中的分布情况。
Objective: To establish a HPLC method to determine the carnosic acid in the stomach and intestine of rats and study its tissue distribution characteristics. Method: After intragastric administration of carnosic acid (90 mg·kg-1), rats for each time point were sacrificed by decapitation. After removal of the blood, various tissues were rapidly removed and weighted, all tissues were treated with a series of pretreatment before HPLC. Chromatographic separation was achieved on a Kromasil C18 column (46 mm×150 mm，5 μm) protected by an ODS guard column at 25 ℃, using acetonitrile 01% phosphoric acid solution (55∶45) as mobile phase, at a flow rate of 1 mL·min-1. The wavelength of the UV detector was set at 210 nm for carnosic acid and internal standard. Result: Good linearities were obtained in every tissue over a range of 0321 2 1606 mg·L-1. The recovery, intra day and inter day precision and accuracy of three concentrations of carnosic acid in tissues met the requirements of methodology. And the stability of the tissue samples were also validated. The results of distribution in stomach and intestine showed that the highest concentration was (3071±1192) μg·g-1 in stomach and (3332±1770) μg·g-1 in intestine after intragastric administration of carnosic acid. Conclusion: The HPLC method was established to determine the concentration of carnosic acid in tissues. This method is quick, precise, and reproducible. It is the first time to study the tissue distribution of carnosic acid in rats after intragastric administration.