[Studies on in vivo release of berberine hydrochloride from carboxymethyl konjac glucomannan pellets in rats].

Objective: To observe the absorption and concentration of berberine hydrochloride (BH) in gastric, entric, colonic tissue after intragastric administration of BH-containing carboxymethyl konjac glucomannan pellets for evaluating colon-specific drug delivery characteristics of the pellets.

Method: BH-containing carboxymethyl konjac glucomannan pellets (pellets group) and BH-containing carboxymethyl cellulose suspension (control group) were intragastric administrated to rats at the dose of 50 mg x kg(-1), respectively. A high performance liquid chromatography method determinated BH concentration in rat plasma and tissue. Drug delivery index (DDI) was calculated.

Result: The range of BH in plasma and tissue in rats were 0.025 2-2.52 mg x L(-1) (r = 0.999 2) and 0.126-25.22 mg x L(-1) (R > 0.99),respectively. The detection of BH in plasma and tissue were 10 microg x L(-1) and 8 microg x L(-1), respectively. The area under the curve (AUC(0 --> infinity)) in the plasma samples of pellets group was 0.477 times that of the control group; in the gastric, entric, colonic tissue, the AUC(0 --> infinity) of pellets group was as much as 0.187, 0.228, 2.00 times that of the control group, respectively. The DDI of the pellets was 0.392 4, 0.478 6, 4.193 in the gastric, entric, colonic tissue of the rat, respectively.

Conclusion: Carboxymethyl konjac glucomannan pellets may be a useful carrier of BH for colon-specific delivery.