Determination of gastrodin in biological specimens and its pharmacokinetics

A reverse-phase high pressure liquid chromatographic method for the simultaneous determination of gastrodin (Gas) and its metabolite, p-hydroxybenzyl alcohol (HBA), in biological specimens was developed. This method was simple, rapid, highly specific and precise. The plasma concentration-time curve of Gas iv in rabbits, rats and dogs was described by the two-compartment open model. The distribution and elimination of Gas was very rapid in animals mentioned above. The biological availability was 79.4% after ig Gas 200 mg/kg to rats, but Gas could not be determined in the plasma of rabbits given at the same dose. However, Gas was assayed in plasma of rabbits after intraduodenal administration, with a biological availability of 2.90%. There was a distinct species specificity in the pharmacokinetic characteristics of Gas among these three species of animals.