Introduction: The most frequently used experimental animals in spinal cord injury (SCI) studies are mice and rats. Recent data demonstrate that therapeutic measures producing positive results in rodents are not effective in humans. That is why authors decided to study behavioral and MRI changes in a porcine SCI model.
Methods: Six (n=6) adult Goettingen-Minnesota (G-M) minipigs of both sexes weighing 32-35 kg were anesthetized, location of laminectomy was determined by help of plain x-rays, then animals were placed into an immobilization frame. The exposed L1 spinal cord segment was compressed by a computer operated 5mm thick circular rod with a peak force 0,8 kg at a velocity of 3cm/sec. During the recovery period, neurological functions were monitored. On the 12th postoperative day minipigs were perfusion fixed and the extent of damage was evaluated by postmortem MRI of dissected spinal cords.
Results: On the 2nd day following 0,8 kg spinal cord compression injury the experimental animals demonstrated an incomplete paraplegia. The neurological deficit improved rapidly and all minipigs showed near normal ambulantion 12 days after SCI. MRI analyses showed loss of spinal white matter integrity and cavitations in epicentre of SCI with longitudinal spreading for one segment cranially and caudally.
Conclusions: The study confirmed reliability and reproducibility of the proposed model of incomplete SCI in minipigs. The MRI changes in the epicentre of injury and in its vicinity did not impede the near complete recovery of neurological functions.
The study was supporetd by a grant of the Agency of the Ministry of Education, Science, Research and Sport of the Slovak republic for the Structural Funds of EU, ITMS 26220220/27.
Patient Care: The application of therapetic measures tested in the minipig SCI model could be used in clincal trials.
Learning Objectives: By the conclusion of this session participants should be able to discuss in small groups problems related to preclinical experimental models of SCI.
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