Underwater shock wave induced lung and brain injuries in canines / 第二军医大学学报

ABSTRACT

[Abstract] Objective To explore underwater shock wave-induced injuries of the lung and brain in canines. Methods Eighteen Beagle dogs were randomly divided into six groups according to the distances to the explosion source control group and 5 experimental groups (5 m, 7 m, 9 m, 11 m and 13 m groups). The animals were exposed to underwater shock wave via a self-designed underwater explosive instrument. The dynamic explosive process was recorded by the underwater high-speed camera. Computed tomography (CT) scans of brain and chest were performed 6 h after injury. Pathological examination and H-E staining for hippocampus and lung were conducted 24 h after injury. The expression levels of interleukin (IL)-6, IL-1β, IL-10, tumor necrosis factor α (TNF-α) and transforming growth factor β (TGF-β) in the hippocampus were measured by immunohistochemical staining. Results The underwater high-speed camera showed that the injury process included blast wave and bubble pulsation. The total mortality of the animals was 40.0% (6/15) in the experimental groups. CT examination revealed no major alterations in the brain of the animals, while there were pleural effusion and pneumothorax in the chest of animals in the experimental groups. H-E staining showed inflammatory cells infiltration in the hippocampal tissue and erythrocyte deposition in the alveoli of animals in the experimental groups. The expression levels of IL-6, IL-1β, IL-10, TNF-α, and TGF-β in the hippocampus of animals in the experimental groups were significantly elevated compared with those in control group (all P0.05). Conclusion Brain and chest are damaged significantly after underwater explosion, which may be the main causes for the death of animals. It is important to elucidate the underlying mechanisms of brain injury caused by underwater explosive wave for the protection of underwater blast injuries.