摘要
To study the biopharmaceutics characteristics of paris saponin Ⅶ(PSⅦ). The solubility of PSⅦ was evaluated by measurement of the equilibrium solubility in different solvents and media. The permeability of PSⅦ was evaluated by measuring the oil/water partition coefficient(lgP_(app)) and determining the apparent permeability coefficient(PC_(app)) on a mono-layer Caco-2 cell model. The effects of p-glycoprotein and multidrug resistance related protein 2 on PSⅦ transport in mono-layer Caco-2 cell model were further investigated. Finally, the small intestinal absorption of PSⅦ was investigated in rat. In solvents of different pH, the equilibrium solubility of PSⅦ was quite low, and the dose number of PSⅦ was larger than 1. The lgP_(app) of PSⅦ was less than 0. The apparent permeability coefficient [PC_(app)(AP-BL)] of PSⅦ in mono-layer Caco-2 cell model was less than 14.96 × 10^(-6) cm·s^(-1), and the efflux ratio of PSⅦ in mono-layer Caco-2 cell model was less than 1. The transport rate of PSⅦ in mono-layer Caco-2 cell model was not affected by the inhibitors of p-glycoprotein and multidrug resistance related protein 2. After oral administration, PSⅦ could be detected in rat intestinal contents, but could not be detected in the small intestinal mucosa. PSⅦ showed low solubility and permeability,which would result in low oral bioavailability in clinic. PSⅦ belonged to Class IV compound in biopharmaceutics classification system.
