Comparative pharmacokinetic studies of Ephedra herba in common cold and nephrotic syndrome rat models

Ephedra herba is a conventional Chinese medicine to treat cold, fever, asthma, edema, and lung diseases in the clinic. At present, most pharmacokinetic studies focus on the pharmacokinetic process of alkaloids in normal animals. However, the non-alkaloid components are also active. In addition, the pharmacokinetic studies under pathological state make more sense for clarifying the material basis of efficacy. In this study, a sensitive and rapid ultra-high-performance-tandem mass spectrometry method was developed and applied to determine nine bioactive components (ephedrine, pseudoephedrine, methylephedrine, (+)-catechin, epicatechin, vitexin, vicenin-2, cinnamic acid, and ferulic acid) in normal, common cold and nephrotic syndrome rats after the oral administration of Ephedra herba. Compared to the normal group, except for ferulic acid, the exposure levels of the other eight components were significantly increased and the plasma clearance clearly declined in common cold rats. Similarly, the exposure levels of seven components other than cinnamic acid and ferulic acid were also significantly augmented and the plasma clearance decreased significantly in nephrotic syndrome rats. In brief, the pathological conditions of the common cold and nephrotic syndrome could lead to alterations in the pharmacokinetics profiles of the nine components, which provide a reference for further exploration of the pharmacodynamics basis of Ephedra herba.