To make clear of the absorbed components of Tianzhusan (TZS) and its possible mechanism in preventing vascular dementia (VD), the rats' models of VD were prepared by a permanent ligation of the bilateral common carotid arteries. After 60 days, rats were administrated with TZS for 0.1 g x kg(-1), and
Gastrodin, parishin and parishin C were purified from a water extract of GE (rhizome of Gastrodia elata, an herb medicine for treatment of neuronal disorders). In order to compare the pharmacological effects of gastrodin, parishin and parishin C on improving cognition deficits, we tested them in an