Tetramethylpyrazine for treatment of experimentally induced stroke in Mongolian gerbils.

Tetramethylpyrazine, a drug originally isolated from the rhizome of Ligusticum walliichi, has been used routinely in China for the treatment of stroke and angina pectoris. We evaluated this drug by testing its effectiveness in increasing the survival rate in a stroke model using Mongolian gerbils. Our results indicate that tetramethylpyrazine can increase survival rate only if it is administered before the induction of cerebral ischemia. Since we administered the drug intraperitoneally, it is possible that pretreatment was necessary to increase its effective concentration in the blood. Receptor binding studies indicated that tetramethylpyrazine was inactive against a variety of pharmacologically active receptors.