RESUMEN
A new rat spinal cord injury model, which uses a modification of a DeBakey aortic aneurysm clamp to create the injury, is presented. The model produces a ventral persisting mass (bone and soft tissue) without the requirement of a prior decompressive operation (laminectomy). Modifications of the original technique have resulted in a nil surgical mortality rate. This technique has been applied to 138 animals. It has produced a consistent percentage of animals with complete myelopathies, as well as incomplete myelopathies and animals without apparent injury. The percent of baseline neurological function lost (change in degrees of the angle of tilt as measured by the inclined plane technique) in each group of surviving animals was 58, 36, and 9%, respectively. Sagittal postmortem sections confirmed mass lesions located ventral to the spinal cord. Histological sections confirmed neuronal loss consistent with the neurological findings.
Asunto(s)
Modelos Animales de Enfermedad , Ratas , Traumatismos de la Médula Espinal/etiología , Animales , Paraplejía/etiología , Paraplejía/fisiopatología , Presión , Ratas Endogámicas , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/fisiopatología , Instrumentos QuirúrgicosRESUMEN
A study of the dose-response effects of naloxone and methylprednisolone after rat ventral spinal cord injury is presented. The spinal cord injury model used herein is unique in that it results in a ventral compression of the spinal cord without the need for a prior laminectomy. This allows for a close approximation of the human clinicopathological situation. There was a statistically significant positive effect on neurological outcome with a naloxone dose of 2.5 mg/kg, whereas higher and lower doses yielded little or no influence on outcome. Methylprednisolone was observed to offer similar results. These results, however, did not achieve statistical significance. The early administration of moderately high doses (45-60 mg/kg), however, offered the best results. The responses to the treatment regimens presented here offer hope for spinal cord injury victims. The observed dose-response relationships indicate that erroneous conclusions may arise from studies using inappropriate doses of narcotic antagonists, as well as other drugs.