| The limb ischemia-reperfusion injury is a common pathophysiological phenomenon in clinical orthopaedics . Once it occurs,it can induce degeneration and necrosis of mucle ,vein and nerve in not severe case. For serious patients,it may be dangerous to the life .The mechanism of limb ischema-reperfusion injury is very complicated ,up to now, not completely elucidated yet. According to the probable mechanism of ischemia-reperfusion injury, the methods,such as hypothermia and low flow reperfusion inhibiting the production of oxygen free radical, eliminating oxygen free radical,anti-leucocyte adhesion ,and ischemic pretreatment,were .applied to treat the injury and had some beneficial effects. However, the prevention and cure of limb ischemia-reperfusion injury are still a difficult problem at present. There are still many problems unsolved. Methylprednisolone is a synthetic glucocorticoid, which has been widely studied in neurosurgery and hepatosurgery in recent years. The results indicated that it possessed properties of anti-lipid superoxidation,inhibiting the production of oxygen free radical, reducing the toxicity of oxygen free radical, and anti-leucocyte adhesion. To our knowledge,there are still no reports that the limb ischemia-reperfusion injury is treated by Methylprednisolone. The objective of this study, in which a model of limb ischemia-reperfusion injury in rabbit is designed, is to ascertain the protective effects of Methylprednisolone on the limb ischemia-reperfusion injury, in order to explore a new approach of prevention and cure of limb ischemia-reperfusion.2. Materials and methodes(1)The model:As Kan Yivan's model of ischemia-reperfusion in limb, femoral vein was dissociated and clamped with blood vessel nip at groin of rabbit's hind limb,while base of thigh was encircled with a rubber band. By this way, all collateral circulation were interdicted.(2) Groups: sixteen New Zealand white rabbits weighting 2.4 kg to 2.7kg randomized into 2 groups. A( experimental group):30mg/kg of Methylprednisolone was infused upon external jugular vein prior to reperfusion. B(control group): 10ml normal saline(N.S) was mfused at the same time.(3) Quantification assay: Value of superoxide dismutase(SOD) and malondialdehyde(MDA) at the time of pre-ischemia^ 5 hours of ischemic, 2 hours of reperfusion and 4 hours of reperfusion . All values are expressed as MEAN + SD . A Value of p<0.05 was considered statistically significant.The changes of histological stain and histopathologic at different time were also observed in the experiment.3.Results and discussion(1)Value of SOD and MDA at time of 5 hours of ischemic. There was no significant change in experimental group than in control group ( 202.5?5.08u/ml , 2.01+0.39 nmol/ml VS 167.36 + 40.93 u/ml, 2.28 + 0.41 nmol/ml, respectively P>0.05) It indicates that experimental group is comparable with control group before reperfusion.(2) In control group Value of SOD in 2 and 4 hours of reperfusion declined than that in 5 hours of ischemia, while value of MDA was contrary(201.99?4.98u/ml , 2.01?.39nmol/ml VS 135.54?55.97u/ml, 2.35?.47nmol/ml, respectively, P<0.05), (201.99?44.98u/ml,2.01?.39nmol/ml VS 84.12?4.18u/ml,2.42 + 0.61 nmol/ml, respectively,P<0.05).It shows damdge of limb is augmented during reperfusion after skeletal muscle ischemia.(3)Value of SOD and MDA at time of 2 and 4 hours of eperfusion :There was significant increasing of SOD and decreasing of MDA inexperimental group than in control group (194.97?53.89u/ml ,1.77 ?.35nmol/ml VS 135.54 ?55.97u/ml,2.35 ?0.47nmol/ml, respectively, P<0.05)(152.71 ?46.61u/ml,1.48 ?0.24nmol/ml VS 84.12?4.12u/ml, 2.42?.61nmol/ml, respective ly, P<0.05). Thesedata indicate that Methylprednisolone is effective in protectionagainst is chemic-reperfusion injury and against lipid peroxidation of limb.(4)Result of histological stainTime of histological stain :A(5 hours of ischemia),B(4 hours of reperfusion in experimental group), C(4 hours of...
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