Intestinal absorption effect of Angelica dahurica extract on puerarin of puerariae Lobatae Radix / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effect of extractive Angelica dahutica on intestinal absorption of puerarin, the mechanism of the absorption enhancement of A. dahutica was investigated, providing a new thread of combinations of the Chinese herbal drugs.</p><p><b>METHOD</b>Everted intestinal sac and in situ single pass perfusion were used to study the effect of gut absorption of puerarin solution containing the extractive A. dahurica as well as the influence of P-gp on the absorption of puerarin, and explore weather the extractive A. dahutica can enhance the absorption of puerarin and the mechanism of absorption of puerarin.</p><p><b>RESULT</b>The puerarin could be absorbed at all of four intestinal segments with increaing absorption amount perunit as follows: ileum > colon > jejunum > duodenum. The absorption of puerarin in jejunum was significantly increased with the extractive A. dahutica in situ single pass perfusion of jejunum. The apparent permeability coefficient (Papp) and absorption rate constant (Ka) of puerarin in the jejunum were descreased gradually with higher concentrations, and the Papp with the Ka of jejunum solution containing the P-gp inhibitor of verapamil were increasing respectively 2.49, 2.60 (P < 0.001) than only the jejunum solution in absorption. The absorption of jejunum in pH 5.0, 6.8 were better than it in pH 7.4.</p><p><b>CONCLUSION</b>The mechanism of absorption of jejunum was active absorption and was effected by P-gp. The extrative A. dahurica can enhance the absorption of the jejunum.</p>

The enhancing effect of Angelica dahurica extracts on absorption of baicalin--the active composition of Scutellaria / 药学学报

To explore the mechanism of the absorption enhancement of Angelica dahurica extract (Ade), the absorption mechanism of baicalin in the Scutcllaria water extraction as well as the effect of Angelica dahurica extract on absorption of baicalin were investigated. In order to determine the main absorption site, everted intestinal sac model was used to study the effect of Angelica dahurica extract on the absorption of baicalin at duodenum, jejunum, ileum and colon. In situ single pass intestinal perfusion model was performed to study the absorption of various concentrations of baicalin and the effect of Angelica dahurica extract on the absorption of baicalin at the main absorption site. To authenticate the consequence of perfusion by getting the blood from the hepatic portal vein and determine the concentration of the baicalin in the blood. The result showed that baicalin could be absorbed at all of the four intestinal segments with increasing absorption amount per unit as follows: ileum > colon > jejunum > duodenum. The absorption ofbaicalin in the duodenum significantly increased with Angelica dahurica extract, thus, duodenum was chosen to be the studying site. Apparent permeability values (Papp) and absorption rate constant (Ka) of baicalin in the duodenum increased gradually with higher concentrations. When the concentration of baicalin rises to a certain degree, the absorption increase had a saturable process, the absorption of baicalin may be an active transportation. Baicalin may be not a substrate of P-gp as verapamil which had not significantly affected the Papp and Ka of baicalin. The absorption of baicalin in the duodenum significantly increased (P < 0.01) in the two models with Angelica dahurica extract and the concentration of baicalin in the blood from the hepatic portal vein showed that the Angelica dahurica extract can increase the absorption of baicalin.