The present study investigated the differences in pharmacokinetics and intestinal absorption of six alkaloids in Sanmiao Pills and Simiao Pills in rats and explored the different efficacies of the two formulae. After oral administration of Sanmiao Pills and Simiao Pills in rats, blood samples were collected at different time points. Samples were prepared for the determination of six alkaloids in plasma by UPLC-MS/MS. The chromatography was performed on an ACE Excel 3 C_(18 )column with acetonitrile-0.1% formic acid in water as the mobile phase for gradient elution. Analytes were detected in the positive ion mode. Plasma concentrations and pharmacokinetic parameters were calculated. Intestinal absorption of alkaloids was investigated by single-pass intestinal perfusion and absorption parameters of ingredients were calculated. The results showed that the UPLC-MS/MS method for simultaneous determination of concentrations of six alkaloids in plasma was developed and validated by methodological investigations, such as specificity, calibration curves, precision, accuracy, recovery, matrix effect, and stability. The results of the pharmacokinetic assay revealed that C_(max) and AUC values of phellodendrine, berberine, magnoflorine, berberrubine, and jatrorrhizine in Simiao Pills were significantly increased, and CL/F values were reduced as compared with those in Sanmiao Pills, which indicated the increase in plasma concentrations of alkaloids. The intestinal absorption parameters K_(a )and P_(eff) values of phellodendrine, berberine, and jatrorrhizine in Simiao Pills were higher than those in Sanmiao Pills. The intestinal absorption and plasma concentrations of alkaloids in Simiao Pills were significantly higher than those in Sanmiao Pills, suggesting that the composition of Simiao Pills was more conducive to the alkaloids into the blood to resist inflammation and lower uric acid.
Keywords: Sanmiao Pills; Simiao Pills; alkaloid; intestinal absorption; pharmacokinetics.