Roles of opioid receptors in the protective effect of limb remote ischemic postconditioning on spinal cord
ZHAO Jiao-mei
OU Ce-hua
ZHOU Jun
LI Gang
Abstract：Objective To investigate mechanism of opioid receptor mediating the protective effects of limb remote ischemic preconditioning on spinal cord in rabbits .Methods Twenty-four New Zealand rabbits were randomly divided into 4 groups (n＝6 per group).Spinal cord ischemia group (SCI): spinal cord ischemia was induced by an infrarenal a-orta clamping for 25 min.Remote ischemia postconditioning group (RIP): postconditioning was induced by 3 conditioning cycles of 5 minutes of ischemia and reperfusion on both hind limbs at 2 min before infrarenal reperfusion .MOR group (MOR) and NAL group (NAL): morphine (1 mg/kg) and naloxone (1 mg/kg) were given, respectively before reperfu-sion.The neural status was scored with the Tarlov criteria 4, 12, 24 and 48 hours after reperfusion.All the animals were sacrificed 48 hours after reperfusion and the spinal cords were harvested immediately for histopathological study .The cor-relation between neurological function after reperfusion (48h) and the number of normal neurons in anterior spinal cord was analyzed.Results Tarlov scores and the number of normal motor neurons in spinal cord anterior horn of RIP group were significantly higher than SCⅡ group 4 h, 12 h, 24 h, 48h after reperfusion (P＜0.05).Tarlov score at 4 h of MOR group was significantly higher than RIP group (P＜0.05), but no statistical significance in Tarlov scores at 12 h, 24 h, 48 h and the number of normal motor neurons in spinal cord anterior horn between the two groups .Tarlov scores and the number of normal motor neurons in spinal cord anterior horn of NAL group were significantly lower than RIP group 4 h, 12 h, 24 h and 48 h after reperfusion (P＜0.05).There was a strong correlation between the final neural function scores and the number of normal motor neurons in the anterior horn of spinal cord (rS＝0.882, P＜0.001).Conclusion Limb re- mote ischemic postconditioning has neuroprotective effects on spinal cord ischemia reperfusion injury in rabbit .The neuro-protection can be restrained by naloxone , implying opioid relates with the mechanism of limb remote ischemic postcondi-tioning against spinal cord ischemic reperfusion injury .
Keywords：spinal cord ischemia reperfusion injurylimb remote ischemic postconditioningopioid receptor
Publication Date：2018-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 1337-1341 )