Ischemic perconditioning on mesenteric ischemia/reperfusion injury in rats

ABSTRACT Purpose: To evaluate if the perconditioning affects the antioxidant capacity in mesenteric ischemia and reperfusion injury. Methods: Twenty-one Wistar rats were assigned into three groups, as follows: Sham, IR and rPER. The animals were subjected to mesenteric ischemia for 30 min. rPER consisted of three cycles of 5-min hindlimb ischemia followed by 5 min hindlimb perfusion at the same time to mesenteric ischemic period. After 5 minutes, blood and 5 cm of terminal ileum were harvested for thiobarbituric acid reactive substances (TBARS) and Trolox equivalent antioxidant capacity (TEAC) measurement. Results: rPER technique was able to reduce intestinal tissue TBARS levels (p<0.0001), but no statistic difference was observed in blood levels between groups, although it was verified similar results in rPER and Sham group. rPER technique also enhanced TEAC levels in both blood (p = 0.0314) and intestinal tissue (p = 0.0139), compared to IR group. Conclusions: rPER appears as the most promising technique to avoid IR injury. This technique reduced TBARS levels in blood and intestinal tissue and promoted the maintenance of antioxidant defense in mesenteric acute injury.

Remote ischemic conditioning protects against testicular ischemia∕reperfusion injury in rats

Abstract Purpose To evaluate the effect of remote ischemic conditioning associated to N-acetylcysteine (NAC) on testicular ischemia∕reperfusion (I∕R) injury in rats. Methods Twenty-five adult male Wistar rats were randomly distributed into five experimental groups (n=5), as follows: Sham, I∕R, Perconditioning (PER), NAC and PER+NAC. Two-hour ischemia was induced by rotating the left testis 720° to clockwise direction, followed by 4 hours of reperfusion. Perconditioning was performed by three I/R cycles of 10 min each on the left limb, 30 min before reperfusion. N-acetylcysteine (150 mg∕kg) was administered 30 min before reperfusion. Results Statistical differences were observed in MDA levels between I/R group with all groups (p<0.01), in addition there was statistical difference between PER and Sham, and PER+ NAC groups (p<0.05) in plasma. Conclusions The protective effect of perconditioning isolated in the reduction of lipid peroxidation related to oxidative stress was demonstrated. However, when Perconditioning was associated with NAC, there was no protective effect against testicular injury of ischemia and reperfusion.

Perconditioning associated to hypertonic saline solution on liver function improvement after ischemia/reperfusion injury

Abstract Purpose: To evaluate the effects of hypertonic saline solution associated to remote ischemic perconditioning in liver ischemia/reperfusion injury in rats. Methods: 25 male rats (Wistar) were distributed into five groups: Sham group (S); Ischemia/Reperfusion group (I/R) with 30 minutes of liver ischemia; Remote ischemic perconditioning group (Per) with three cycles of 10 minutes of I/R performed during liver ischemia; Hypertonic saline solution group (HSS) treated with hypertonic saline solution (4ml/kg); Remote ischemic perconditioning + Hypertonic saline solution group (Per+HSS) with both treatments. Results: Per+HSS group showed a lower degree of liver dysfunction in relation to I/R group, whereas the technique of remote ischemic perconditioning isolated or associated with saline solution significantly improved liver function and reduced histological damage. Conclusion: Remote ischemic perconditioning associated or not to saline solution promoted reduction of acute liver injury induced by ischemia/reperfusion.

Effects of hypertonic saline solution associated to remote ischemic perconditioning in kidney ischemia/reperfusion injury in rats

Abstract Purpose: To evaluate the effects of hypertonic saline solution associated to remote ischemic perconditioning in renal ischemia/reperfusion injury in rats. Methods: Twenty five male rats (Wistar) underwent right nephrectomy and were distributed into five groups: Sham group (S); Ischemia/Reperfusion group (I/R) with 30 minutes of renal ischemia; Remote ischemic perconditioning group (Per) with three cycles of 10 minutes of I/R performed during kidney ischemia; Hypertonic saline solution group (HSS) treated with hypertonic saline solution (4ml/kg); remote ischemic perconditioning + Hypertonic saline solution group (Per+HSS) with both treatments. After reperfusion, blood samples were collected for BUN and creatinine serum levels analyzes. TBARS were evaluated in plasma and renal tissue to assess oxidative stress. Kidney histopathological examination were performed. Results: Per+HSS group showed a lower degree of renal dysfunction in relation to I/R group, whereas the technique of remote ischemic perconditioning isolated or associated with saline solution significantly reduced oxidative stress and histological damage. Conclusion: Remote ischemic perconditioning associated or not to saline solution promoted reduction of acute renal injury induced by ischemia/reperfusion.

Influence of remote ischemic conditioning and tramadol hydrochloride on oxidative stress in kidney ischemia/reperfusion injury in rats

Abstract Purpose: To evaluate the effects of tramadol hydrochloride associated to remote ischemic perconditioning on oxidative stress. Methods: Twenty five male rats (Wistar) underwent right nephrectomy and were distributed into five groups: Sham group (S); Ischemia/Reperfusion group (I/R) with 30 minutes of renal ischemia; Remote ischemic perconditioning group (Per) with three cycles of 10 minutes of I/R performed during kidney ischemia; Tramadol group (T) treated with tramadol hydrochloride (40mg/kg); remote ischemic perconditioning + Tramadol group (Per+T) with both treatments. Oxidative stress was assessed after 24 hours of reperfusion. Results: Statistical differences were observed in MDA levels between I/R group with all groups (p<0.01), in addition there was difference between Tramadol with Sham, Per and Per+T groups (p<0.05), both in plasma and renal tissue. Conclusion: Remote ischemic perconditioning was more effective reducing renal ischemia-reperfusion injury than administration of tramadol or association of both treatments.

Effects of nitrofurazone on correction of abdominal wall defect treated with polypropylene mesh involved by fibrous tissue

PURPOSE:Toevaluate the effects of nitrofurazone on the correction of abdominal wall defect treated with polypropylene mesh involved by fibrous tissue in rats.METHODS: A defect in the abdominal wall was created and corrected with polypropylene mesh in 20 rats. They were randomly distributed into four groups: control, fibrous mesh, nitrofurazone and nitrofurazone dip in the mesh. Euthanasia was performed in 21 post-operative days. The healing process was analyzed regarding the meshes and macroscopic and microscopic aspects.RESULTS:All animals had adhesions. However, no statistically significant difference (p>0.05) when compared between groups. Similarly microscopic analysis, in which there was no statistical significance level for the evaluated parameters such as mono and polymorphonuclear lymphocytes, granuloma, fibrosis, necrosis and collagen proliferation.CONCLUSION:There was no significant effect on the abdominal wall defect repair with polypropylene mesh surrounded by fibrous tissue when dipped in nitrofurazone 2%.