Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators of Inflammation to Ameliorate the Deleterious Effects of Blast Overpressure on Eye and Brain Visual Processing Centers in Rats

摘要

Using an adult rat model of blast wave exposure, we rigorously characterized the cellular and functional damage to the eyes (retinas) and brain visual processing centers, by electroretinography (ERG), visual discrimination behavioral testing, and histopathology. Blast wave injury was carried out by placing the rats in a compressed air driven shock tube and exposing them, in a right side on orientation, once to a 20 psi (260 Hz) blast over pressure wave. Rats were assessed at baseline and then 1, 7, and 14 days post-exposure. By 7 to 14 days out, blasted rats versus shams showed significantly decreased ERG waveform amplitudes for the right side eyes (approximately 30% less; n = 15 vs.14), a trend for impaired ability to visually discern a cue light to earn food rewards (approximately 30% less; n = 10 vs. 11), and significant neuronal cell degeneration within the right side retinas and both brain optic tracts (2 and 3-fold more, respectively; n = 11 vs. 11). ERG and histopathology results significantly correlated with each other (r = - 0.7). There also was a strong relationship between the retina and brain optic tract cell damage (r = 0.8). Overall, our findings demonstrate that blast wave exposure leads to loss of vision in rats, likely through retinal cell death followed by anterograde degeneration of brain visual processing centers from lack of signaling input.