Cerebral penetrating arterioles (PAs) are structurally and functionally different from the pial arterioles, as they are an exception group from the collateral circulation. Previous study has demonstrated the PAs are the bottlenecks to the flow from the surface arteries to the deeper microcirculations. However, functional change in PAs after ischemia plays an important role in delivering blood from a highly collateralized pial arteriole network to capillaries. An ability to separately monitor PA flow dynamics is critical to understand flow redistribution mechanism during stroke and refine stroke treatment target. We use optical coherence tomography (OCT)-based microangiography (OMAG) to evaluate flow and velocity change in multiple PAs after middle cerebral artery occlusion (MCAO) in mice across a large cortex region, covering distal branches of arterioles and anastomosis. We also apply OCT-based tissue injury mapping (TIM) method to reveal the potential penumbra development within the imaging region, upon which we observed apparent differences of the PA flow dynamics between core and penumbra regions. Our results suggest that the flow dynamics of PAs can be an important factor regulating the stroke penumbra development, and that stimulatory treatment targeting PAs can be studied under the guidance of OMAG.
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