Liver Damage Caused By Explosion Of Tbe And Tnt Explosive

The shake wave caused by all kinds of blasts can lead to a stress and endocrine disturbance. Endocrine disturbance can result in pathological changes of organs regulated by enuroendocrine system. Thermobaric explosive (TBE) can destroy the biological and other targets by producing strong shock wave,above 2000℃high temperature and serious oxygen shortage of the surroundings. There is an important military value and practical significance to investigate its biological effects. Up to now there is a little data about its effects on biological targets. In present study, rats and goats were used to study the damage effects of liver injury after explosion of TBE explosive and trinitro tolune (TNT) explosive. The injury characteristics of liver in the two explosives was compared. The results may provide the theoretically and experimental evidences for the prevention and treatment of its injury.Methods:1. Thermobaric and TNT explosive were provided and enforced detonation by×××××. 2. Animal groups: 50 healthy goats (10-15kg) and 50 male SD rats (180-220g) were provided by experimental animal centre of FMMU. The animals were divided into Thermobaric group and TNT's group, 25 goats in each group, standing right side to the explosion center, the specific semi-diameter R0 was selected by 0.03 MPa of human moderately-damaged rule. The animals were placed in fan-shaped areas of 1/4R0, 1/2 R0, 3 /4R0, R0, 5/4 R0 and 1.5R0 far away from the center, respectively. The SD rats, freely in the cages, were placed R0 far away from the explosion center, control animals were placed at 4 km far away from the explosion center. All goats were killed by exsanguination after explosion to observe injury of organs. The rats were killed at 12 hours and 1 month after explosion.3. Animals survival rate: The survival condition was observed 5 min after TBE and TNT static explosion respectively. The animals whose function of heart and breathing stopped were anatomied. The survival animals were exsanguigated by cutting carotid artery within 2 hours after explosion. The morphological features were investigated.4. Animals were investigated at immediately, 12 hours and 1 month after explosion. Liver tissues were fixed by 10% (v/v) formaldehyde, 30 g/L Glutaraldehyde and 1% (w/v) Osmium tetraoxide, respectively. The sample preparation were carried out for light microscopy and electron microscopy.5. The reticular fibers, collagen fibers, elastic fibers and mast cells were analyzed by special staining methods.Results:1.The survival situation after TNT and TBE static explosionBoth TBE and TNT's static explosion can destroy animals,and the type of injury was combined injury, primarily blast injury. The more far away from the explosion centre,the lesser damage degree was. Lethality rate caused by TBE was more serious than TNT in the same volume with TBE. 2. The morphological features of goats'liver after TNT and TBE static explosionThe histopathological changes of the liver after TNT and TBE static explosion includes vacuolar degeneration, congestion of sinusoid, obvious hemorrhage. Meanwhile, congestion, hemorrhage, infiltration of inflammatory cells, necrosis of bile duct epithelial cells were discovered in portal areas. And infiltration of neutrophilic granulocytes appeared in the livers of animals which not died instantly. The injury area and degree of liver caused by TBE was more serious than that exposed to TNT.3. The goats'liver ultrastructure after TNT and TBE static explosionThe impairment of the ultrastructure of liver which includes obvious congestion, increase of Kupffer cells, and infiltration of neutrophilic granulocytes and lymphocytes after TNT and TBE static explosion. There were increasing lysosomes and myeloid membranous figures. The swelling, malformation and indistinct cristae of mitochondria as well as dilation of endoplasmic reticulum were also found.4. The changes of collagen,elastic,reticular fibers and mast cells after TNT and TBE static explosionElastic fibers were maily distributed in the blood vessels of the portal areas at 12 h group after TNT and TBE static explosion. A part of broken elastic fibers were found in TBE group. Collagen fibers changed minorly, which mainly distributed in the interstitial areas in the portal areas and the surroundings of the central veins. Reticular fibers were distributed widely in the portal areas, the surroundings of the central veins and intrahepatic cord and connected each other to form reticula. In 1 month group, elastic fibers appeared in the surroundings of the blood vessels in the portal areas and the central veins. It increased obviously. Collagen fibers increased significantly in TNT and TBE groups. Collagen fibers distributed between hepatocytes except in the portal areas and the surroundings of the central veins, and they were more obvious in TBE group. Reticular fibers extensively were distributed in the two groups, they can confuse each other, twist to form an irregularly shaped mass. It was more obvious in TBE group.5. The relationship between liver fibrosis and mast cells after TNT and TBE static explosionMast cells were mainly distributed in the surroundings of the blood vessels in the portal areas at 12 h after TNT and TBE static explosion, and the mast cells were also occasionally seen in the surroundings of the central veins. In 1 month group, there was a great of mast cells appeared in the surroundings of the blood vessels and interlobular bile ducts in the portal areas both in TNT and in TBE groups . A large number of mast cells appeared in the surroundings of the central veins. The degranulation of mast cells was also found, and it was more obvious in TBE than TNT groups.Conclusion:1. There was serious acute damage on liver and also apparent delayed effect,such as liver fibrosis after TBE and TNT static explosion. The basis of liver fibrosis was infiltration of inflammatory cells and proliferation of fibers in liver. And, the damage by TBE was more severe than that by TNT.2. Infiltration of inflammatory cells in liver was the important reason that lead to the liver fibrosis, because a variety of inflammatory cells can release different cytokines which could induce fibrosis. There was closely relationship between chronic inflammation, mast cell proliferation and liver fibrosis.