Intestinal absorption effect of Angelica dahurica extract on pueririn of Puerariae Lobatae Radix

Abstract

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. 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. 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. 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.