Severity-dependent expression of pro-inflammatory cytokines in traumatic spinal cord injury in the rat

• Published in: Journal of clinical neuroscience Vol. 12; no. 3; pp. 276 - 284
• Main Authors: Yang, Liqun, Jones, Nigel R., Blumbergs, Peter C., Van Den Heuvel, Corinna, Moore, Emma J., Manavis, Jim, Sarvestani, Ghafar T., Ghabriel, Mounir N.
• Format: Journal Article
• Language: English
• Published: Scotland Elsevier Ltd 01-04-2005
• Subjects: Animals; Cytokines - metabolism; Fluorescent Antibody Technique; Inflammation - metabolism; Inflammation - pathology; inflammatory response; Interleukin-1 - metabolism; interleukin-1β; interleukin-6; Interleukin-6 - metabolism; Male; microglia; Nerve Tissue Proteins - biosynthesis; Nerve Tissue Proteins - genetics; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - biosynthesis; Spinal Cord - pathology; Spinal Cord Injuries - metabolism; Spinal Cord Injuries - pathology; traumatic spinal cord injury; Tumor Necrosis Factor-alpha - metabolism; tumour necrosis factor-α; inflammatory response; tumour necrosis factor-α; traumatic spinal cord injury; microglia; interleukin-6; interleukin-1β
• ISSN: 0967-5868; 1532-2653
• DOI: 10.1016/j.jocn.2004.06.011

The post-traumatic inflammatory response in acute spinal cord contusion injury was studied in the rat. Mild and severe spinal cord injury (SCI) was produced by dropping a 10 g weight from 3 and 12 cm at the T12 vertebral level. Increased immunoreactivity of TNF-α in mild and severe SCI was detected in neurons at 1 h post-injury, and in neurons and microglia at 6 h post-injury, with a less significant increase in mild SCI. Expression was short-lived and declined sharply by 1 d post-injury. RT-PCR showed an early significant up-regulation of IL-1β, IL-6 and TNF-α mRNAs, maximal at 6 h post-injury with return to control levels by 24 h post-injury, the changes being less statistically significantly in mild SCI. Western blot showed early transient increases of IL-1β, IL-6 and TNF-α proteins in severe SCI but not mild SCI. Immunocytochemical, western blotting and RT-PCR analyses suggest that endogenous cells (neurons and microglia) in the spinal cord, not blood-borne leucocytes, contribute to IL-1β, IL-6 and TNF-α production in the post-traumatic inflammatory response and that their up-regulation is greater in severe than mild SCI.