Effect of Borneol on the Distribution of Danshensu to the Eye in Rabbit via Oral Administration

Abstract

Purpose: Both borneol and danshensu are bioactive substances derived from traditional Chinese medicine. In this paper, the effect of borneol on the distribution of danshensu to the eyes in rabbits via oral administration was investigated.Methods: The rabbits were injected danshensu (1.0 g/kg) into the auris dextra vein 15 min after intragastric administration of borneol and the danshensu concentrations in plasma, aqueous humor, and vitreous humor were measured by high-performance liquid chromatography. Draize test was used to examine the eye irritation.Results: Compared with the administration of danshensu alone, danshensu concentrations co-administrated with borneol in plasma were between 60.99 and 722.90 μg/ml. Peak times (Tmax) in both groups appeared at 0 min; however, compared with the control group, the values were not statistically significant although they differ (P > 0.05). The concentrations of danshensu in aqueous humor and vitreous humor in test group are higher than that in control group. The difference was statistically significant (P < 0.05). Tmax in both groups appeared at 25 min. Neither irritation nor inflammatory reaction was found during the examinations.Conclusion: The results suggest that the promoting effect of borneol on the permeability of drugs through the blood–ocular barrier in vivo is obvious, which indicates that borneol has the potential to be used as an ocular penetration enhancer.