Objective: Directed by meridian distribution of Radix Scutellariae

studying effector substance of Qingkailing injection. Method: Qingkailing injection was given to experimental rats

the brain

liver and lung were collected in various time. Then Qingkailing was injected to both normal and cerebral isehemia-reperfusion rats

the brain

liver and lung were collected at various time. The concentration of baicalin from samples was determined by HPLC-MS. Result: After iv Qingkailing injection

considerable baicalin was distributed quickly to target tissue of normal rats

ie liver and lung; the content of baicalin in the brain was minimum. In cerebral ischemia-reperfusion rats

the concentration of baicalin in the brain was higher than that of normal rats. Conclusion: Baicalin is one of effector substance of Qingkailing injection curing lung

liver and cerebral ischemia disease. It is feasibility to search for effector substance of complex prescription

directed by meridian distribution of traditional Chinese medicine.