Primary changes in the rat’s hippocampus after exposure to an air blast wave
DOI:
https://doi.org/10.14739/2310-1237.2025.3.340916Keywords:
explosion, trauma, brain, hippocampus, electron microscopy, primary changesAbstract
To identify the primary ultrastructural changes in the CA1 region of the rat`s hippocampus after a single exposure to an air blast wave.
Materials and methods. The study was conducted on healthy 12 sexually mature male Wistar rats weighing 220-270 g, kept under standard conditions in the vivarium of Dnipro State Medical University. The animals were randomly divided into two groups: experimental (n = 6) and sham (n = 6). The rats of experimental group were exposed to an air blast wave with a pressure of 30.1 ± 2.9 kPa. One hour after exposure to the blast wave, animals in both groups were anaesthetised with halothane and euthanised, followed by craniotomy, removal of the hippocampus and conducted electron microscopic examination using standard procedures. All manipulations were carried out in accordance with the rules of current legislation on bioethical treatment of experimental animals.
Results. It was established that a single exposure to a blast wave with a pressure of 30.1 ± 2.9 kPa resulted in mild trauma, as indicated by the absence of cell membrane rupture with cytoplasm and organelles escaping into the extracellular space and the absence of complete vessel rupture with massive haemorrhages. Signs of primary neuronal injury included increased nuclear membrane permeability and nuclear chromatin rarefaction, significant perinuclear oedema, cytoplasmic vacuolisation, and extracellular oedema. Damage to the blood-brain barrier vessels was detected in the form of perivascular oedema, thickening and delamination of the vessel membrane due to its oedema, and cavitation bubbles were present in the vascular lumen. Nerve fibres were also traumatized, as indicated by myelin delamination.
Conclusions. It has been established that swelling of neurons and increased permeability of the nucleus membrane and its oedema, as well as delamination of myelin fibres (a decrease in the sphericity coefficients of axonal profiles by 11 % (p < 0.05) and dendritic profiles by 33 % (p < 0.01) in the hippocampus of experimental rats). Signs of primary injury due to the impact of the blast wave were found on the side of the blood-brain barrier in the form of perivascular oedema, thickening and delamination of the vascular membrane due to its oedema (47 % increase in the relative area of electron-transparent sections (p < 0.01) of the hippocampus of experimental rats). The presence of a cavitation bubble in the hippocampus vessel indicates the persistence of the initial damage due to its ability to cause hydraulic shocks.
References
Zhang L, Yang Q, Yuan R, Li M, Lv M, Zhang L, et al. Single-nucleus transcriptomic mapping of blast-induced traumatic brain injury in mice hippocampus. Sci Data. 2023;10(1):638. doi: https://doi.org/10.1038/s41597-023-02552-x
Evans LP, Roghair AM, Gilkes NJ, Bassuk AG. Visual Outcomes in Experimental Rodent Models of Blast-Mediated Traumatic Brain Injury. Front Mol Neurosci. 2021;14:659576. doi: https://doi.org/10.3389/fnmol.2021.659576
Chen S, Siedhoff HR, Zhang H, Liu P, Balderrama A, Li R, et al. Low-intensity blast induces acute glutamatergic hyperexcitability in mouse hippocampus leading to long-term learning deficits and altered expression of proteins involved in synaptic plasticity and serine protease inhibitors. Neurobiol Dis. 2022;165:105634. doi: https://doi.org/10.1016/j.nbd.2022.105634
Pierce ME, Hayes J, Huber BR, Jeromin A, Fortier CB, Fonda JR, et al. Plasma biomarkers associated with deployment trauma and its consequences in post-9/11 era veterans: initial findings from the TRACTS longitudinal cohort. Transl Psychiatry. 2022;12(1):80. doi: https://doi.org/10.1038/s41398-022-01853-w
Cifu DX. Clinical research findings from the long-term impact of military-relevant brain injury consortium-Chronic Effects of Neurotrauma Consortium (LIMBIC-CENC) 2013-2021. Brain Inj. 2022;36(5):587-97. doi: https://doi.org/10.1080/02699052.2022.2033843
Rutter B, Song H, DePalma RG, Hubler G, Cui J, Gu Z, et al. Shock Wave Physics as Related to Primary Non-Impact Blast-Induced Traumatic Brain Injury. Mil Med. 2021;186(Suppl 1):601-9. doi: https://doi.org/10.1093/milmed/usaa290
Orr TJ, Lesha E, Kramer AH, Cecia A, Dugan JE, Schwartz B, et al. Traumatic Brain Injury: A Comprehensive Review of Biomechanics and Molecular Pathophysiology. World Neurosurg. 2024;185:74-88. doi: https://doi.org/10.1016/j.wneu.2024.01.084
Schmitt R, Qayum S, Pliss A, Kuzmin AN, Muthaiah VP, Kaliyappan K, et al. Mitochondrial Dysfunction and Apoptosis in Brain Microvascular Endothelial Cells Following Blast Traumatic Brain Injury. Cell Mol Neurobiol. 2023;43(7):3639-51. doi: https://doi.org/10.1007/s10571-023-01372-2
Ma J, Wang J, Deng K, Gao Y, Xiao W, Hou J, et al. The Effect of MaxiK Channel on Regulating the Activation of NLRP3 Inflammasome in Rats of Blast-induced Traumatic Brain Injury. Neuroscience. 2022;482:132-42. doi: https://doi.org/10.1016/j.neuroscience.2021.12.019
Shi QX, Chen B, Nie C, Zhao ZP, Zhang JH, Si SY, et al. Improvement in cognitive dysfunction following blast induced traumatic brain injury by thymosin α1 in rats: Involvement of inhibition of tau phosphorylation at the Thr205 epitope. Brain Res. 2020;1747:147038. doi: https://doi.org/10.1016/j.brainres.2020.147038
Guilhaume-Correa F, Pickrell AM, VandeVord PJ. The Imbalance of Astrocytic Mitochondrial Dynamics Following Blast-Induced Traumatic Brain Injury. Biomedicines. 2023;11(2):329. doi: https://doi.org/10.3390/biomedicines11020329
Miranda EG, Nascimento VP, Waisberg DR, Sousa MW, Lima MF, Silva Ddos S, et al. Inhalation anesthesia equipment for rats with provision of simultaneous anesthetic and oxygen. Acta Cir Bras. 2011;26(2):140-3. doi: https://doi.org/10.1590/s0102-86502011000200012
Kozlova YV, Abdul-Ogly LV, Kosharnyi AV, Kytova IV, Korzachenko MA, inventors. Prystrii dlia doslidzhennia dii na orhanizm udarnoi khvyli vybukhu [Device for studying the effect of an explosion shock wave on the body]. Ukrainian patent UA 146858. 2021 Mar 24. Available from: https://sis.nipo.gov.ua/uk/search/detail/1584578/
Kuo J, editor. Electron microscopy: Methods and protocols. 2nd ed. New York, NY: Humana Press; 2007. Available from: http://dx.doi.org/10.1007/978-1-59745-294-6
Belimenko MS, Kosharnyi VV, Abdul-Ogli LV, Kushnareva KA. [Ultrastructural changes in the myocardium in the action of general hypothermia]. Visnyk problem biolohii i medytsyny. 2021;(1):197-201. Ukrainian. doi: https://doi.org/10.29254/2077-4214-2021-1-159-197-201
Schindelin J, Arganda-Carreras I, Frise E, Kaynig V, Longair M, Pietzsch T, et al. Fiji: an open-source platform for biological-image analysis. Nat Methods. 2012;9(7):676-82. doi: https://doi.org/10.1038/nmeth.2019
NACLAR. National advisory committee for laboratory animal research, guidelines on the care and use of animals for scientific purposes. 2nd ed. Washington (DC): National Academies Press; 2022.
Parisi F, Degl'Innocenti S, Aytaş Ç, Pirone A, Cantile C. Morphological and Immunohistochemical Changes in Progressive Postmortem Autolysis of the Murine Brain. Animals (Basel). 2024;14(24):3676. doi: https://doi.org/10.3390/ani14243676
Packer JM, Bray CE, Beckman NB, Wangler LM, Davis AC, Goodman EJ, et al. Impaired cortical neuronal homeostasis and cognition after diffuse traumatic brain injury are dependent on microglia and type I interferon responses. Glia. 2024;72(2):300-21. doi: https://doi.org/10.1002/glia.24475
Nehring SM, Tadi P, Tenny S. Cerebral edema. [Updated 2023 Jul 3]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537272/
Kawoos U, Abutarboush R, Gu M, Chen Y, Statz JK, Goodrich SY, et al. Blast-induced temporal alterations in blood-brain barrier properties in a rodent model. Sci Rep. 2021;11(1):5906. doi: https://doi.org/10.1038/s41598-021-84730-8
Whitehead B, Corbin D, Meadows E, Zhang N, Hollander JM, Karelina K, et al. Cerebral hypoperfusion exacerbates vascular dysfunction after traumatic brain injury. Exp Neurol. 2024;380:114907. doi: https://doi.org/10.1016/j.expneurol.2024.114907
Marsh JL, Bentil SA. Cerebrospinal Fluid Cavitation as a Mechanism of Blast-Induced Traumatic Brain Injury: A Review of Current Debates, Methods, and Findings. Front Neurol. 2021;12:626393. doi: https://doi.org/10.3389/fneur.2021.626393
Yu X, Nguyen TT, Wu T, Ghajari M. Non-Lethal Blasts can Generate Cavitation in Cerebrospinal Fluid While Severe Helmeted Impacts Cannot: A Novel Mechanism for Blast Brain Injury. Front Bioeng Biotechnol. 2022;10:808113. doi: https://doi.org/10.3389/fbioe.2022.808113
Dougan CE, Song Z, Fu H, Crosby AJ, Cai S, Peyton SR. Cavitation induced fracture of intact brain tissue. Biophys J. 2022;121(14):2721-9. doi: https://doi.org/10.1016/j.bpj.2022.06.016
Mahoney SO, Chowdhury NF, Ngo V, Imms P, Irimia A. Mild Traumatic Brain Injury Results in Significant and Lasting Cortical Demyelination. Front Neurol. 2022;13:854396. doi: https://doi.org/10.3389/fneur.2022.854396
Downloads
Additional Files
Published
How to Cite
Issue
Section
License
Copyright (c) 2025 Yu. V. Kozlova, S. V. Kozlov
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
