An approach for studying the direct effect of shock waves on neuronal cell structure and function.

Recent U.S. military conflicts have underscored the knowledge-gap regarding blast-induced traumatic brain injury (bTBI). In vitro models of TBI, have the advantage of following the neuronal response to biomechanical perturbations in real-time that can be exceedingly difficult in animal models. Here we sought to develop an in vitro approach with controlled blast biomechanics to study the direct effects of the primary shock wave at the neuronal level. An in-vitro blast injury apparatus that simulates human anatomy was developed. Primary neuronal cells from Sprague-Dawley rat embryos were cultured inside the apparatus. On day 10 in vitro the neuronal cultures were exposed to 70 kPa peak blast overpressure using helium gas in a blast tube. Incident pressure as well as apparatus pressure were measured. 24hrs post injury cell viability was measured. We were able to successfully blast injured cells without detaching them and caused a significant change in viability from a single blast. The Model also allowed adjustable level of bTBI based on the cover thickness which is an added value not present in other bTBI models. Results also stress the importance of pressure wave frequency as a significant factor for cell viability in bTBI. For the same peak pressure cell can survive low frequency wave even if they have higher amplitude.