大鼠在体单向肠灌流模型研究石榴皮多酚中鞣花酸的肠吸收动力学

Intestinal absorption dynamics study on ellagic acid of pomegranate peel polyphenols by in situ single-pass perfusion model in rats

目的考察石榴皮多酚中鞣花酸的大鼠在体肠吸收动力学特征。方法采用大鼠在体单向肠灌流模型,选用HPLC法测定灌流液中鞣花酸在大鼠不同肠段以及在不同质量浓度下的吸收情况。结果鞣花酸在不同肠段均有吸收,在实验浓度范围内,大鼠十二指肠、空肠、回肠和结肠中鞣花酸单体的吸收速率常数(Ka)分别为4.44×10^(-2)~7.11×10^(-2)/min、6.58×10^(-2)~8.60×10^(-2)/min、5.61×10^(-2)~7.02×10^(-2)/min、3.92×10^(-2)~5.95×10^(-2)/min;石榴皮多酚精制物中鞣花酸的Ka分别为7.00×10^(-2)~7.81×10^(-2)/min、6.32×10^(-2)~7.96×10^(-2)/min、4.97×10^(-2)~5.58×10^(-2)/min、3.50×10^(-2)~4.68×10^(-2)/min。鞣花酸单体和石榴皮多酚精制物中的鞣花酸的Ka和表观渗透系数(P_(app))差异有统计学意义(P<0.05)。结论鞣花酸在大鼠肠道内不存在特殊"吸收窗",石榴皮多酚精制物中的其他成分可能对鞣花酸的吸收有促进作用,在不同肠段鞣花酸的质量浓度对K_a和P_(app)值影响不大,吸收机制可能为主动转运。

Objective To study the intestinal absorption kinetics of ellagic acid of pomegranate peel polyphenols in rats. Methods A single-pass intestinal perfusion model was used to measure the intestinal absorption of ellagic acid in different absorption segments and the content of ellagic acid was assayed by HPLC method. The effect of mass concentrations on intestinal absorption was detected. Results Ellagic acid could be absorbed in the whole intestine,and its absorption rate was influenced by the intestinal segments. The absorption rate of ellagic acid in duodenum,jejunum,ileum and colon was 4. 44 ×10^-2～ 7. 11 ×10^-2/ min,6. 58 ×10^-2～ 8. 60 ×10^-2/ min,5. 61 ×10^-2～7. 02 ×10^-2/ min,3. 92 ×10^-2～ 5. 95 ×10^-2/ min,respecvticvely; The absorption rate of ellagic acid in pomegranate peel polyphenols purification in duodenum,jejunum,ileum and colon was 7. 00 ×10^-2～ 7. 81 ×10^-2/ min,6. 32 ×10^-2～ 7. 96 ×10^-2/ min,4. 97 ×10^-2～ 5. 58 ×10^-2/ min,3. 50 ×10^-2～ 4. 68 ×10^-2/ min respecvticvely. The Ka and Papp of ellagic acid monomers and the ellagic acid in pomegranate peel polyphenols extraction have significant difference（ P〈0. 05）. Conclusion Ellagic acid has no a special＂absorption window＂. Some compositions of polyphenol extractions may have played a catalytic role in ellagic acid＇s absorption. The concentrations have little influence on Ka and Papp of ellagic acid in different absorption segments. The absorption of ellagic acid may active transport in the general intestinal segments.