A patient experiencing an ischemic stroke receives intravenous thrombolytic therapy (tPA) within the therapeutic window. Which mechanism best explains the potential conversion to a hemorrhagic stroke during reperfusion?

💡 Explanation

Reperfusion after ischemia can lead to hemorrhagic transformation because the restoration of blood flow causes matrix metalloproteinase (MMP) activation, which degrades the blood-brain barrier. Therefore, this disruption increases the risk of hemorrhage, rather than the other options which would be neuroprotective.

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