Thursday, August 13, 2020

Peri-Infarct Hot-Zones Have Higher Susceptibility to Optogenetic Functional Activation-Induced Spreading Depolarizations

What the hell is being done with this knowledge to help survivors recover?

Peri-Infarct Hot-Zones Have Higher Susceptibility to Optogenetic Functional Activation-Induced Spreading Depolarizations

Originally publishedhttps://doi.org/10.1161/STROKEAHA.120.029618Stroke. 2020;51:2526–2535

Background and Purpose:

Spreading depolarizations (SDs) are recurrent and ostensibly spontaneous depolarization waves that may contribute to infarct progression after stroke. Somatosensory activation of the metastable peri-infarct tissue triggers peri-infarct SDs at a high rate.

Methods:

We directly measured the functional activation threshold to trigger SDs in peri-infarct hot zones using optogenetic stimulation after distal middle cerebral artery occlusion in Thy1-ChR2-YFP mice.

Results:

Optogenetic activation of peri-infarct tissue triggered SDs at a strikingly high rate (64%) compared with contralateral homotopic cortex (8%; P=0.004). Laser speckle perfusion imaging identified a residual blood flow of 31±2% of baseline marking the metastable tissue with a propensity to develop SDs.

Conclusions:

Our data reveal a spatially distinct increase in SD susceptibility in peri-infarct tissue where physiological levels of functional activation are capable of triggering SDs. Given the potentially deleterious effects of peri-infarct SDs, the effect of sensory overstimulation in hyperacute stroke should be examined more carefully.

Footnotes

For Sources of Funding and Disclosures, see page 2534.

The Data Supplement is available with this article at https://www.ahajournals.org/doi/suppl/10.1161/STROKEAHA.120.029618.

Correspondence to: Cenk Ayata, MD, PhD, Massachusetts General Hospital, Harvard Medical School, 149 13th St, 6408, Charlestown, MA 02129. Email

 

No comments:

Post a Comment