PRETREATMENT WITH THE ENDOTOXIN LPS ENHANCES RECOVERY IN RATS AFTER A CONTUSION INJURY. J.M.Olson*; G.Garcia; S.N.Washburn; R.C.Miranda; J.W.Grau. Dept Psychol, Medical Anatomy, Texas A&M Univ, College Station, TX, USA
Prior studies have found that noxious stimulation and illness can alter spinal cord function. For example, both can induce an NMDA-mediated central sensitization that enhances nociceptive reactivity. We have shown noxious stimulation also undermines behavioral potential in spinally transected rats and hurts recovery after a spinal cord injury. The present study examines the impact of a single systemic treatment of lipopolysaccharide (LPS), an endotoxin that leads to the release of proinflammatory cytokines. While past studies suggest chronic long-term treatment with LPS after injury can have a beneficial effect (Guth et. al, 1994, Exp Neurol, 126, 76-87), we hypothesized acute pretreatment would, like shock, engage a destructive process that hinders recovery. Twenty-four hours prior to contusion surgery rats were injected with either saline or LPS (50 mg/kg IP). The next day rats were anesthetized with pentobarbital and the spinal cord was injured using the NYU impactor (12.5mm drop). Recovery was assessed over the next six weeks using the BBB scale (Basso et. al, 1995, J. Neurotrauma, 12, 1-21). Rats pretreated with LPS recovered greater locomotor function (p < .05) Results show that pretreatment with LPS has a paradoxical protective effect that resembles the beneficial effects associated with long-term treatment.
Supported by: MH60157 & NS41548 to JWG and RCM
J.M.Olson, G.Garcia, S.N.Washburn, R.C.Miranda, J.W.Grau. PRETREATMENT WITH THE ENDOTOXIN LPS ENHANCES RECOVERY IN RATS AFTER A CONTUSION INJURY. Program No. 800.6. 2002 Abstract Viewer/Itinerary Planner. Washington, DC: Society for Neuroscience, 2002. CD-ROM.