MMP9 and stroke disorder: This study yielded the following main findings: MLR-HFS, started three hours after induction of a photothrombotic stroke in the sensorimotor cortex of rats and applied continuously for 24 h (i) did not improve nor worsen the hampered BBB due to ischemia; (ii) had no impact on the expression of three main components of the BBB—claudin 3, claudin 5, and occludin; and (iii) had no impact on the expression of pro-MMP-9.