Abstract:

The main active components of Rhubarb are anthraquinones (AQs), most of which are glycosides and others are free. The concentrations of AQs derivatives (rhein, aloe-emodin, emodin, chrysophanol and physcion) in plasma and homogenate were assayed with a high performance liquid chromatography (HPLC) method. The pharmacokinetic parameters and distribution of Rhubarb AQs in rabbits or rats were studied after administrationof different formulas. Elimination of AQs was fit to a two-compartment model in rats and rabbits. There were no significant difference in the main pharmacokinetic parameters between rhein and AQs in rats. AQs were distributed progressively in the kidney, liver, blood, and heart. The AQs were mainly composed of rhein in vivo and was excreted by the kidney. For formulas that contained Rhubarb, rhein could be used as a probe for in vivo pharmacokinetic studies.

Key words: Rhubarb, Anthraquinones, Pharmacokinetics, Distribution