The present study focused on the biologic effects of tempol on anti-inflammatory and nitric oxide generation in contusion spinal cord injury (SCI). The animal model of SCI was induced by dropping a 10-g rod (2.0 mm in diameter) at a height of 25 mm. Tempol was injected intraperitoneally a dose of 100 mg/kg at 15 min before SCI. Controls was injected with saline. The contused spinal segments were removed according to time courses, and the expression level of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) was analyzed along with the size of irreversibly damaged region. After SCI, the relative amounts of COX-2 and iNOS mRNA were peaked at 8 h after post-injury, and then decreased up to 7 days post-injury, and normal level at 14 days. Expression of COX-2 protein was peaked at 8 h post-injury. With the tempol pre-treatment, the immunoreactivity of COX-2 and nitrotyrosine in paraffin-embedded tissue slices was profoundly decreased. The irreversibly damaged area of the spinal cord was peaked at 3 days after SCI. With tempol pre-treatment, the irreversibly damaged area shows a statistically significant decrease at 3 days after SCI. These evidences indicate that tempol pre-treatment reduces irreversibly damaged area on the contusion SCI in rat. The mechanisms of biologic reactions of tempol might be related to the decreased expressions of COX-2 and iNOS in spinal cord cells, neurons and glia. It is expected that the tempol effect on the SCI is not only antioxidant activity but also anti-inflammatory reaction.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.