Establishment of incomplete spinal cord ischemic injury rabbit models and their significance

Abstract

Objective To explore the establishment of animal models of incomplete spinal cord ischemic injury to provide ideal carriers for researching the pathogenesis of incomplete spinal cord ischemic injury.Methods Twenty-four New Zealand rabbits were randomly divided into a control group (n=8) and 2 experimental groups (n=16); control group only underwent sham-operation without inducing spinal cord injury to exclude the influences of anesthesia and surgery on motor evoked potential (MEP); in the experimental groups,spinal cord ischemia injury models were established by the methods of selective ligation of segmental spinal artery from cranio-caudal direction.Baseline MEP after anesthetization were recorded,and the MEP 30 min,2 and 7 d after vascular ligation were noted.Motor function was assessed after narcotic conscious,and 2 and 7 d after vascular ligation.The specimens 7 d after ligation were taken for HE staining.Results The amplitude of MEP in the experimental group having 3 lumbar artery ligation 30 minutes after ligation was significantly different as compared with that in the control group (P＜0.05); no significant differences on the amplitude of MEP were noted between these 2 groups 2 and 7 d after ligation (P＞0.05).Significant differences on the amplitude of MEP were noted between control group and experimental group having 4 lumbar artery ligation 30 min,and 2 and 7 d after ligation (P＜0.05).The latency of all these rabbits showed no significant difference 30 min,and 2 and 7 d after ligation (P＞0.05).The amplitude changes of MEP were accorded with the results of motor function scale.Conclusion Reversible incomplete spinal cord ischemia animal models can be established after 3 lumbar artery ligation; irreversible incomplete spinal cord ischemia animal models can be established after 4 lumbar artery ligation. Key words: Spinal cord injury; Animal model; Lumbar