The therapeutic effects of Agmatine, Methylprednisolone and Rapamycine on experimental spinal cord injury and evaluate with light, electronmicroscopy and biochemical datas

Spinal cord injury is an important social and economic problem. Tissue damageoccurs with two mechanisms as primary and secondary injury. Necrosis appears asan outcome of primary injury. Secondary injury occurs in following hours such asdisturbed circulation, deteriorated conditions with inflammatory response, impairedmetabolism, electrolyte imbalance, oxidative stress due to free oxygen radicals,apoptosis and excitotoxicity. Secondary injury became target of therapies because ofthese mechanisms can be preventive. In the present study it was aimed that toexamine the effects of rapamycine, methylprednisolone and agmatine onexperimental spinal cord injury in rat by biochemical, light and electron microscopicevaluations. Our study was performed with 30 Spraque Dawley adult female rats.There were 5 groups as Sham control, Injury, Injury+methylprednisolone, Injury+Rapamycine, Injury+ Agmatine. Following the induction of trauma to T7-8 levels,treatment was given everyday for a week. At the end of the time, medulla spinalisand blood samples were collected from sacrificed animals. Hematoxylene- Eosine,Luxol Fast Blue and TUNEL immunreaction for apoptosis staining were performedfor light microscopical evaluations. The ultrastructure of injured medulla spinalistissues were evaluated. Although edema, degeneration of neuron, akson and myelinwere significant in injury group, the integrity of structure was well-arranged intreatment groups. Our study showed that, methylprednisolone and agmatine preventslipid peroxidation by reducing MDA levels, rapamisin increased it. In SOD andcatalase levels, there is no significant difference among the groups. Mostlyrapamisin and also agmatine decreased the orther antioxidant enzyme glutathioneperoxidase levels which attributed to response to free oxygene radicals. Thebiochemical results showed that, rapamycine significantly decreased SOD and GPxlevels, but increased MDA levels; Agmatine decreased GPx levels but not significantalteration occured in SOD levels. As a result, all treatment groups of spinal cordinjury decreases secondary response but not prevent completely.KEY WORDS: Spinal cord injury, Methylprednisolone, Rapamycine, Agmatine