A rat model of spinal cord ischemic injury

Phillip Tomas Guillen, MD, Varun Kesherwani, PhD, Kyle S. Nelson, MD, Sandeep K. Agrawal, PhD


There is a need of ischemic model of spinal cord injury to identify the therapeutic window for intervention of ischemic injury in humans. Calcium for long has been known to be a key source of neuronal damage during ischemic injury. The purpose of this study is to develop an in vivo model of spinal cord ischemia in rats and to confirm the functionality of the model by studying the expression pattern of inositol 1,4,5-triphosphate receptor isoform 1 (IP3R1) and ryanodine receptor isoform 2 (RyR2). Ischemic injury was induced by clamping the aorta below the azygous vein using thoracotomy approach for 27 minutes. Behavioral and histopathologic studies were done at 0, 2, 4, 8, and 48 hours after injury. Eighteen rats suffered from complete paralysis and two showed perceptible movement of the joints of their hind limbs. There was no paralysis in five animals (Sham Group). Histopathology with hemotoxylin and eosin stain at 8 and 48 hours demonstrated neuronal cell loss and diffused neuronal necrosis. Glial fibrillary acidic protein staining showed severe reactive gliosis. Apoptosis was also visualized at 48 hours of ischemia. Expression of IP3R1 and RyR2 was upregulated after ischemic injury and expression of RyR2 increased until 8 hours after injury, while the maximum expression of IP3R1 was observed 4 hours after injury. This preliminary study confirmed that this model of ischemic spinal cord injury causes paralysis and significant changes in neurology and histopathology with time. Increased expression of IP3R1 and RyR2 confirms the functionality of the model by showing increased intracellular calcium levels.

Keywords: Calcium, Ischemic injury, Spinal cord, Rat model


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Agrawal SK, Nashmi R, Fahlings MG: Role of L- and N-type calcium channels in the pathophysiology of traumatic spinal cord white matter injury. Neuroscience. 2000; 99: 179-188.

Toung TJ, Chang Y, Williams M, et al.: Experimental spinal cord ischemia: Model characterization and improved outcome with arterial hypertension. Crit Care Med. 2004; 32: 1346-1351.

Zivin JA, DeGirolami U: Spinal cord infarction: A highly reproducible stroke model. Stroke. 1980; 11(2): 200-202.

Kiziltepe U, Turan NN, Han U, et al.: Resveratrol, a red wine polyphenol, protects spinal cord ischemia-reperfusion injury. J Vas Surg. 2004; 40: 138-145.

Agrawal SK, Fehlings MG: Mechanisms of secondary injury to spinal cord axons in vitro: Role of Na+, Na(+)-K(+)-ATPase, the Na(+)-H+ exchanger, and the Na(+)-Ca2+ exchanger. J Neurosci. 1996; 16: 545-552.

Coston A, Laville M, Baud P, et al.: Aortic occlusion by a balloon catheter: A method to induce hind limb rigidity in rats. Physiol Behav. 1983; 30: 967-969.

Kanellopoulos GK, Kato H, Hsu CY, et al.: Spinal cord ischemic injury. Development of a new model in the rat. Stroke. 1997; 28: 2532-2538.

Stys PK: White matter injury mechanisms. Curr Mol Med. 2004; 4(2): 113-130.

Stys PK, Ransom BR, Waxman SG, et al.: Role of extracellular calcium in anoxic injury of mammalian central white matter. Proc Natl Acad Sci USA. 1990; 87(11): 4212-4216.

Tekkök SB, Goldberg MP: AMPA/kainate receptor activation mediates hypoxic oligodendrocyte death and axonal injury in cerebral white matter. J Neurosci. 2001; 21(12): 4237-4248.

Waxman SG, Black JA, Ransom BR, et al.: Protection of the axonal cytoskeleton in anoxic optic nerve by decreased extracellular calcium. Brain Res. 1993; 614(1-2): 137-145.

LoPachin RM Jr, Stys PK: Elemental composition and water content of rat optic nerve myelinated axons and glial cells: Effects of in vitro anoxia and reoxygenation. J Neurosci. 1995; 15(10): 6735-6746.

Stys PK, Lehning E, Saubermann AJ, et al.: Intracellular concentrations of major ions in rat myelinated axons and glia: Calculations based on electron probe X-ray microanalyses. J Neurochem. 1997; 68(5): 1920-1928.

Thorell WE, Leibrock LG, Agrawal SK: Role of RyRs and IP3 receptors after traumatic injury to spinal cord white matter. J Neurotrauma. 2002; 19(3): 335-342.

McPherson PS, Campbell KP: Characterization of the major brain form of the ryanodine receptor/Ca2+ release channel. J Biol Chem. 1993; 268(26): 19785-19790.

Otsu K, Willard HF, Khanna VK, et al.: Molecular cloning of cDNA encoding the Ca2+ release channel (ryanodine receptor) of rabbit cardiac muscle sarcoplasmic reticulum. J Biol Chem. 1990; 265(23): 13472-13483.

Kushnir A, Betzenhauser MJ, Marks AR: Ryanodine receptor studies using genetically engineered mice. FEBS Lett. 2010; 584: 1956-1965.

Klegeris A, Choi HB, McLarnon JG, et al.: Functional ryanodine receptors are expressed by human microglia and THP-1 cells: Their possible involvement in modulation of neurotoxicity. J Neurosci Res. 2007; 85: 2207-2215.

Simpson PB, Holtzclaw LA, Langley DB, et al.: Characterization of ryanodine receptors in oligodendrocytes, type 2 astrocytes, and O-2A progenitors. J Neurosci Res. 1998; 52: 468-482.

Ouardouz M, Coderre E, Basak A, et al.: Glutamate receptors on myelinated spinal cord axons: I. GluR6 kainate receptors. Ann Neurol. 2009; 65(2): 151-159.

Kesherwani V, Agrawal SK: Regulation of inositol 1,4,5-triphosphate receptor, type 1(IP3R1) in hypoxic injury of white matter. Neurol Res. 2012; 34(5): 504-511.

Kesherwani V, Agrawal SK: Upregulation of RyR2 in hypoxic/ reperfusion injury. J Neurotrauma. 2012; 29(6): 1255-1265.

Tomes DJ, Agrawal SK: Role of Na(+)-Ca(2+) exchanger after traumatic or hypoxic/ischemic injury to spinal cord white matter. Spine J. 2002; 2(1): 35-40.

Tarlov IM: Spinal Cord Compression: Mechanism of Paralysis and Treatment. Springfield, IL: Charles C Thomas, 1957.

Gale K, Kerasidis H, Wrathall JR: Spinal cord contusion in the rat: Behavioral analysis of functional neurologic impairment. Exp Neuro. 1985; 88: 123-134.

Mattson MP, LaFerla FM, Chan SL, et al.: Calcium signaling in the ER: Its role in neuronal plasticity and neurodegenerative disorders. Trends Neurosci. 2000; 23: 222-229.

DOI: https://doi.org/10.5055/jndr.2013.0008


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