Aim: To investigate the development of fibrotic glial scar with modified post-operative care in compression model of spinal cord injury in adult rats by using aneurysm clip compression.

Methodology: 10 healthy male adult Sprague Dawley rats, an average of 3 months old and weighing 250-300 gm, were randomly divided into AI & AII groups based on experiment duration. Group A1 rats were assessed after 14 days, and Group AII rats after 28 days of spinal cord injury. Rats were given isoflurane inhalation anaesthesia, and surgical exposure spinal cord at the T7 level was performed. An aneurysm clip having 70 g closing force was applied to the T7 level of the spinal cord for 1 minute and then released. Wound closure was done in separate layers, and rats were allowed to recover. Post-operative antibiotics administration was reduced to only one dose of ceftriaxone 2gm/kg and buprenorphine was replaced by tramadol intraperitoneal to avoid injection site abscess and other complications. Ringer’s lactate administration route was also changed from subcutaneous to intra-peritoneal to maintain hemostasis and prevent dehydration.

Results: Microscopic examination of the injury site stained with H & E and Masson’s Trichrome stains, showed significant injury at the aneurysm clip application site in the spinal cord with disturbed cytoarchitecture and high inflammatory cell infiltration. Glial scar formation with central fibrotic core was prominent in injury lesions. All animals showed no sign of infection, surgical wound abscess or any other complication and survived well throughout the experimental duration after changing the route of drug administration from subcutaneous to intra-peritoneal.

Conclusion: Microscopic assessment shows that the aneurysm clip compression method for developing the spinal cord injury model is a reproducible, modest and low-cost model to study glial scar formation in rodents. Only a single dose of a strong antibiotic through intra-peritoneal route administration post-operatively is sufficient to avoid infections and injection site abscess on the condition that proper hygiene, diet, humidity and the surrounding temperature are maintained. 

Keywords: Aneurysm Clip Compression Model, Masson”s Trichrome, Glial Fibrotic Scar