Subcellular Distribution of Tanshinone IIA in Rat Lung and Liver

Objective To study the subcellular distribution of tanshinone IIA in rat lung and liver.Methods After intravenous administration of 6 mg/kg tanshinone IIA,the rats were sacrificed after dosing.Cell fractions of the lung and liver tissue were produced by differential centrifugation.Tanshinone IIA concentrations were determined using the validated LC-MS/MS method.Results Tanshinone IIA concentrations in lung and its organelles were much higher than that in liver and its organelles after administration.Tanshinone IIA in liver and its organelles was predominantly presented as glucuronidated metabolites,while the concentrations of unchanged tanshinone IIA were slightly higher than that of glucuronided form in lung and its organelles.There was no selective drug accumulation in liver organelles.Additionally,tanshinone IIA accumulated in light mitochondria in lung organelles.Conclusion The light mitochondria is the major accumulation site for tanshinone IIA in rat lung organelles,which is the possible mechanism of high concentration accumulation of tanshinone IIA in rat lung.