Comparative pharmacokinetic and bioavailability studies of three salvianolic acids after the administration of Salviae miltiorrhizae alone or with synthetical borneol in rats

Salviae miltiorrhizae is one of the most commonly used herbal plants in the treatment of numerous ailments including cardiovascular diseases for hundreds of years. According to the theory of traditional Chinese herbal medicine, S. miltiorrhizae is always used in combination with borneol to obtain better pharmacological effects. The purpose of this study was to investigate the effects of borneol on the pharmacokinetic and bioavailability of S. miltiorrhizae. The pharmacokinetics studying on rosmarinic acid, salvianolic acid A and salvianolic acid B which are the main active compounds of S. miltiorrhizae in rat plasma, was achieved using a optimal high-performance liquid chromatographic technique coupled with liquid-liquid extraction method. After administration of either single salvianolic acids or salvianolic acids in combination with borneol, plasma concentrations of rosmarinic acid, salvianolic acid A and salvianolic acid B of male Sprague-Dawley rats were determined at different time points (5, 10, 20, 30, 45, 60, 90, 120, 180, 240, 300, and 360 min). In comparison with salvianolic acid extract alone, there were statistically significant differences in pharmacokinetic parameters of rosmarinic acid, salvianolic acid B and salvianolic acid A, and the bioavailability of the three salvianolic acids increased by different degrees when the salvianolic acid extract and borneol were administered together. These results indicated that borneol could enhance the intestinal absorption, decrease the distribution and inhibit the metabolism of salvianolic acids.