A Neuronal Apoptosis Model induced by Spinal Cord Compression in Rat
Summary
Here, we present a protocol to generate a rat spinal cord compression model, assess its behavioral score, and observe the compressed spinal cord region. The behavioral assessments showed decreased monitor motor disability. Hematoxylin and eosin staining and immunostaining revealed considerable neuronal apoptosis in the compressed region of the spinal cord.
Abstract
As a severe progressive degenerative disease, cervical spondylotic myelopathy (CSM) has a poor prognosis and is associated with physical pain, stiffness, motor or sensory dysfunction, and a high risk of spinal cord injury and acroparalysis. Thus, therapeutic strategies that promote efficient spinal cord regeneration in this chronic and progressive disease are urgently needed. Effective and reproducible animal spinal cord compression models are required to understand the complex biological mechanism underlying CSM. Most spinal cord injury models reflect acute and structural destructive conditions, whereas animal models of CSM present a chronic compression in the spinal cord. This paper presents a protocol to generate a rat spinal cord compression model, which was further evaluated by assessing the behavioral score and observing the compressed spinal cord region. The behavioral assessments showed decreased monitor motor disability, including joint movements, stepping ability, coordination, trunk stability, and limb muscle strength. Hematoxylin and eosin (H&E) staining and immunostaining revealed considerable neuronal apoptosis in the compressed region of the spinal cord.
Introduction
As a common progressive degenerative disease, CSM accounts for 5-10% of all cervical spondylosis1. If patients suffering from CSM ignore their symptoms and fail to treat them in a timely and effective manner, this could lead to severe complications, such as spinal cord injury and limb paralysis, which would deteriorate with aging, posing a substantial economic and mental burden to patients and their families2,3. The pathogenesis of CSM is complex, involving static and dynamic factors, the hypoxia-ischemia theory, endothelial cell injury, the blood spinal cord barrier destruction theory, and the inflammation and apoptosis theory4,5,6,7.
The static and dynamic mechanisms of compression on the spinal cord cause clinical symptoms. Protruding vertebral discs, deformed vertebral bodies, and calcified ligaments may cause prolonged spinal cord compression, which will gradually affect the blood-spinal cord barrier and local microvasculature in the spinal cord4,8. In turn, ischemia, inflammation, and apoptosis affect the neurons, axons, and glial cells6,9.
The experimental animal models of spinal cord injury include contusive injury, compressive injury, traction injury, photochemical-induced injury, and ischemia-reperfusion injury. Most of these models also reflect some acute and structural destructive conditions (transection or chemical toxicity). However, these animal models of CSM cannot present progressive neuronal apoptosis in the spinal cord.
This paper describes a detailed protocol to generate a rat spinal cord compression model, which was further evaluated by assessing the behavioral score and observing the compressed region of the spinal cord. This rat spinal cord compression model is a reliable animal model for further investigation of the mechanisms involved in CSM.
Protocol
Representative Results
Discussion
The goal of this surgical procedure was to generate reproducible, prolonged, neural apoptosis in the rat spinal cord. A key advantage of this model is that the expandable hydrogel implants provide a prolonged compression on the spinal cord, thereby leading to a progressive neural apoptotic response (Figure 2C), which is consistent with the pathological process of CSM. In the current study, the mortality from spinal cord injury was extremely low (~2 in 50), whereas the repeatability of t…
Disclosures
The authors have nothing to disclose.
Acknowledgements
This study was supported by the National Key R&D Program of China (2018YFC1704300), National Natural Science Foundation of China (81930116, 81804115, 81873317, and 81704096), Shanghai Sailing Program (18YF1423800), Natural science Foundation of Shanghai (20ZR1473400). This project was also supported by the Shanghai University of Traditional Chinese Medicine (2019LK057).
Materials
| Antibiotic ointment | Prevent wound infection | ||
| Buprenorphine-SR | Pain relief | ||
| Isoflurane | Veteasy | Anesthesia | |
| Inhalant anesthesia equipment | Anesthesia | ||
| Micro ophthalmic forceps | Mingren medical equipment | Length: 11 cm, Head diameter: 0.3 mm | Clip the muscle |
| Ophthalmic forceps | Shanghai Medical Devices (Group) Co., Ltd. Surgical Instruments Factory | JD1050 | Clip the skin |
| Ophthalmic scissors (10 cm) | Shanghai Medical Devices (Group) Co., Ltd. Surgical Instruments Factory | Y00030 | Skin incision |
| SD male rats | Shanghai SLAC Laboratory Animal Co., Ltd | SCXK2018-0004 | Animal model |
| Sterile surgical blades (22#) | Shanghai Pudong Jinhuan Medical Products Co., Ltd. | 35T0707 | Muscle incision |
| Small animal trimmer | Hair removal | ||
| Veet hair removal cream | RECKITT BENCKISER (India) Ltd | Hair removal | |
| Venus shears | Mingren medical equipment | Length: 12.5 cm | Muscle incision |
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