Tissue distribution study of periplocin and its two metabolites in rats by a validated LC-MS/MS method

Periplocin is a cardiac glycoside and has been used widely in the clinic for its cardiotonic, anti-inflammatory and anti-tumor effects. Although it is taken frequently by oral administration in the clinic, there have been no reports demonstrating that periplocin could be detected in vivo after an oral administration, so there is an urgen need to determine the characteristics of periplocin in vivo after oral administration. In this study, a sensitive and reliable liquid chromatography-tandem mass spectrometry method was developed and validated to identify and quantify periplocin and its two metabolites in rat tissue after a single dosage of perplocin at 50 mg/kg. The results demonstrated that periplocin and its two metabolites were detected in all of the selected tissues; periplocin could reach peak concentration quickly after administration, while periplocymarin and periplogenin reached maximum concentration > 4.83 h after administration. The tissue distribution of analytes tended to be mostly in the liver, and higher analyte concentrations were found in the heart, liver, spleen, lung and kidney, but a small amount of chemical constituents was distributed into the brain. The consequences obtained using this method might provide a meaningful insight for clinical investigations and applications.