Direct evidence of acute, massive striatal dopamine release in gerbils with unilateral strokes

Dopamine release into the extracellular space was measured with in vivo electrochemical detection in the ipsilateral and contralateral striata in Mongolian gerbils that suffered a stroke after acute unilateral carotid artery ligations. A sevenfold increase in the dopamine signal occurred within 15 minutes of carotid ligation in the ischemic side, while the unlesioned side had no significant change. Increased extracellular levels of dopamine persisted throughout the 3-hour recording period. Pretreatment with alpha-methyl-p-tyrosine 6 hours prior to recording significantly attenuated the signal increase. This study is the first direct demonstration of the marked, continuous dopamine release that occurs during acute cerebral ischemia.