Vascular Permeability Changes in Experimental Brain Concussion

Validation of Acoustic Wave Induced Traumatic Brain Injury in Rats

“…In addition, TBI models consistently exhibited many damaged neurons manifesting as dark cells [ 33 , 34 , 35 ]. As the intensity of the acoustic wave increased from 3.4 bar to 5.0 bar, so did the number of observable dark neurons, consistent with the other blast intensity [ 33 ] and controlled cortical impact TBI studies [ 28 ]. Finally, sheering of the cortex tissue and opening the blood–brain barrier, appeared to recruit macrophages that have phagocytized blood products to the region, which has been also seen in fluid percussion injury models [ 18 ].…”

“…TBI injury causes pyknosis, defined as when neurons condense and become darkly stained cells [33,34]. Other studies have observed similar results with dark neurons expressing apoptotic proteins Bax, BCl2 and cleaved caspase-3 [28]. Other experiments have identified the presence of jellyfish microglia that are activated after TBI insult and are part of the inflammatory process responsible for neuroprotection and reparative are cells, aiding in neuronal recovery [35].…”

“…TBI is initially a vascular injury in nature [ 28 ] as trauma causes damage to blood vessels that supply neural tissue with nutrients. The rupturing of the blood–brain barrier leads to inflammation, which is responsible for the headaches and dizziness in human patients.…”

“…Quantification of the TBI infarct area was determined by the disruption of condensed dark cells. These dead cells can be easily visualized by their shrunken, condensed, dark staining nuclei and are located along the periphery of the infarct area [ 28 ]. The damaged cortical area surrounding the TBI was traced by following the boundary of these peripheral dark cells.…”