Cilostazol attenuates spinal cord ischemia-reperfusion injury in rabbits

Abstract

Objective: The aim of this study was to evaluate the pretreatment effect of cilostazol on spinal cord ischemia-reperfusion injury.

Design: Prospective, interventional study.

Setting: Research laboratory, single institution.

Participants: Twenty-four New Zealand white rabbits.

Interventions: Twenty-four rabbits were divided into 3 equal groups: group I (sham), group II (ischemia-reperfusion, control group), and group III (cilostazol, administered orally 30 mg/kg/day for 3 days before the surgery). Spinal cord ischemia was induced by clamping the aorta both below the left renal artery and above the iliac bifurcation for 30 minutes. Seventy-two hours postoperatively, the motor function of the lower limbs was evaluated in each animal according to the modified Tarlov score. Spinal cord and blood samples were taken for histopathologic and biochemical analyses at the 72nd hour of reperfusion.

Measurements and main results: All rabbits in the ischemia-reperfusion group (group II) showed severe neurologic deficits. The median (IQR) Tarlov scores postoperatively at 72 hours in groups I, II, and III were 5.0(-), 2.0(1.0), and 4.5(1.0), respectively. Administration of cilostazol resulted in a significant reduction in motor dysfunction when compared with the ischemia-reperfusion group (p<0.001). In the ischemia-reperfusion group, serum and tissue glutathione peroxidase and superoxide dismutase activity were significantly less compared with the sham group (group I) (p<0.05). Serum and tissue glutathione peroxidase and superoxide dismutase levels in the cilostazol-treated group (group III) were higher compared with the ischemia-reperfusion group (p<0.05). In the cilostazol-treated group, serum and tissue malondialdehyde levels were lower compared with the ischemia-reperfusion group (p<0.05). Histopathologic analysis found decreased neuronal injury in the cilostazol group when compared with the ischemia-reperfusion group (p< 0.05).

Conclusions: This study showed that pretreatment with cilostazol significantly ameliorated neurologic functional outcome and attenuated neuronal histopathologic injury after transient aortic occlusion in rabbits.

Keywords: cilostazol; ischemia-reperfusion injury; paraplegia; spinal cord; spinal cord protection.