Aortic occlusion by a balloon catheter: a method to induce hind limb rigidity in rats

Post-ischaemic spinal extensor or flexor rigidity can be induced in different species by clamping or ligature of the descending aorta after thoracotomy or laparotomy. A similar motor deficit can also be induced by an intraluminal aortic occlusion produced by inflation of a balloon attached to the tip of a catheter inserted via the femoral artery. This method is easy to perform and avoids all the possible complications of thoracotomy or laparotomy. In rats the occlusion time for obtaining the maximum percentage of animals exhibiting a permanent hind limb extensor (62.5%) or flexor (12.5%) rigidity was 15-16 minutes. A marked depression of hind limb sensory perception accompanied this rigidity but there were no urinary, bowel or skin disturbances. The unilateral femoral ligation following the catheterization did not induce a difference in muscle tone between both hind limbs. The present procedure which is simpler than other published procedures might thus serve as a useful animal model for spastic paraplegia.