Vascular Response to Spreading Depolarization Predicts Stroke Outcome

Area of Science:

• Neuroscience
• Cerebrovascular physiology
• Stroke research

Background:

• Cortical spreading depolarization (CSD) is a wave of neuro-glial depolarization.
• In stroke, CSD drives neuronal damage by propagating from the ischemic core through the penumbra.
• Vascular responses to CSD in ischemia remain incompletely understood.

Purpose of the Study:

• To investigate the hemodynamic characteristics of CSD in a mouse stroke model.
• To correlate vascular responses to CSD with infarct size and neurological outcome.
• To evaluate the impact of thrombolysis on CSD-induced vascular changes.

Main Methods:

• Used a thrombin-induced stroke model in mice.
• Simultaneously employed in vivo electrophysiology and laser speckle contrast imaging.
• Assessed neurological deficits and infarct size (2,3,5-triphenyltetrazolium chloride staining).

Main Results:

• Observed two distinct patterns of spreading hyperemia: penumbral and full hemisphere.
• Penumbra-confined hyperemia correlated with severe damage, while full hemisphere hyperemia indicated better outcomes.
• Recombinant tissue-type plasminogen activator (r-tPA) altered vascular responses and reduced lesion volume.

Conclusions:

• Spontaneous spreading hyperemia patterns post-ischemia predict stroke injury severity and outcome.
• Modulating hemodynamic responses to CSD presents a potential therapeutic strategy for stroke.
• Understanding CSD's vascular effects is crucial for improving stroke treatment.