Luan Li-biao, Zhao Nuan
Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
Yao Xue Xue Bao. 2006 Feb;41(2):138-41.
To investigate the intestinal absorption of silybin (SLB) in male rats.
Single-pass intestinal perfusion (SPIP) technique was performed in each isolated region of the small intestine at a flow rate of 0.1 mL x min(-1). The samples of perfusate and portal plasma were collected at the designated periods of time after rat intestinal perfusion and analyzed for drug by HPLC.
The absorption rate constant (k(a)) and the effective permeability (P(eff)) of SLB at 190 microg x mL(-1) were determined for each segment. These data indicated the absorption rate were duodenum > jejunum > ileum > colon. SPIP was also performed in duodenum with three concentrations of SLB (80, 190 and 300 microg x mL(-1)). The concentration dependent changes of k(a) and P(eff) were evident in the duodenum perfusion of silybin. At silybin perfusate concentrations of 80 microg x mL(-1), k(a) and P(eff) were different from the values at either of the two higher concentrations (190 and 300 microg x mL(-1), P < 0.05). However there was no difference between 190 microg x mL(-1) and 300 microg x mL(-1) groups. The drug mass appearing in the plasma further indicated the absorption were duodenum > jejunum > ileum > colon.
SLB can be absorbed in whole intestinal sections. When the concentration raises to a certain level, the uptake of SLB will not increase.
研究水飞蓟宾（SLB）在雄性大鼠肠道中的吸收情况。
采用单通道肠道灌注（SPIP）技术，以0.1 mL×min⁻¹的流速在小肠的每个分离区域进行实验。在大鼠肠道灌注后的指定时间段收集灌注液和门静脉血浆样本，并用高效液相色谱法分析药物。
测定了各肠段在190 μg×mL⁻¹水飞蓟宾时的吸收速率常数（k(a)）和有效渗透率（P(eff)）。这些数据表明吸收速率为十二指肠＞空肠＞回肠＞结肠。还在十二指肠中用三种浓度的水飞蓟宾（80、190和300 μg×mL⁻¹）进行了SPIP实验。水飞蓟宾十二指肠灌注中k(a)和P(eff)的浓度依赖性变化明显。在水飞蓟宾灌注液浓度为80 μg×mL⁻¹时，k(a)和P(eff)与两种较高浓度（190和300 μg×mL⁻¹）中的任何一种的值不同（P＜0.05）。然而，190 μg×mL⁻¹组和300 μg×mL⁻¹组之间没有差异。血浆中出现的药物量进一步表明吸收情况为十二指肠＞空肠＞回肠＞结肠。
水飞蓟宾可在整个肠道段被吸收。当浓度升高到一定水平时，水飞蓟宾的摄取量不会增加。
