If a stroke patient receives tPA to dissolve a thrombus, but experiences subsequent brain tissue damage despite successful reperfusion, which mechanism most likely explains the paradoxical injury?

💡 Explanation

Excitotoxicity can occur during reperfusion after tPA treatment because the sudden restoration of blood flow can cause a massive release of glutamate, overstimulating neurons. This leads to neuronal damage. Therefore, excitotoxicity explains the injury, rather than increased metabolism or reduced blood flow, which would have different effects.

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