Postconditioning effect in the hepatic ischemia and reperfusion in rats

Carlos Henrique Marques Dos Santos,Diogo Iengo Nakamura,Luciana Nakao Odashiro Miiji,Cesar Augusto Vendas Galhardo,Sandra Maura Aguena,José Carlos Dorsa Vieira Pontes

doi:10.1590/s0102-86502010000200008

Carlos Henrique Marques Dos Santos, Diogo Iengo Nakamura + Show 4 more

Open Access

https://doi.org/10.1590/s0102-86502010000200008

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Abstract

To evaluate the effect of postconditioning protection in liver tissue of rats submitted to ischemia and reperfusion. 25 Wistar male rats were randomized in three groups: Group A (ischemia and reperfusion - I/R), with 10 rats, which was made ischemia by vascular clamp application in hepatic hilum for 30 minutes and reperfusion for 60 minutes by removal of the clamp; Group B (Postconditioning - IPo), with 10 rats, with same procedure plus postconditioning (3 cycles of reperfusion inserted by 3 cycles of ischemia, 30 seconds for each phase, between ischemia and reperfusion phases); and Group C (Sham), with 5 rats, which took place only laparotomy and manipulation of the hepatic hilum. Specimens were examined (histological evaluation) and dosage of serum AST and ALT was made. The statistical analysis was made with t Student test, with significant difference when p<0.05. In the Sham group there was no histological or enzymatic changes; In group A the mean tissue lesion was 1.6 and in group B 1.1 (p=0.014). In group A the mean ALT level was 355U/l and in group B was 175.9U/l (p=0.016). The mean of AST was 828.8U/l in group A and 295.5U/l in group B (p=0.001). The postconditioning was able to minimize the severity of liver injury in rats submitted to ischemia and reperfusion.

Highlights

The operations of the liver, especially the resection and transplantation, are usually performed with temporary occlusion of the hepatic hilum to prevent bleeding
The IPr made by Murry et al.[8] was of great value in this respect, and served as the inspiration for the creation of the IPo described by Zhao et al.[7], which has been used successfully in situations of ischemia and reperfusion
Elevated levels of AST and ALT is observed experimentally in hepatic ischemia and reperfusion[2,14], which is observed in group I/R of this research, whereas in the Sham group there was no elevation of these enzymes

Summary

Introduction

The operations of the liver, especially the resection and transplantation, are usually performed with temporary occlusion of the hepatic hilum to prevent bleeding This occlusion leads to ischemia followed by reperfusion, which can cause damage to hepatocytes and distance, often worsening the clinical situation of patients[1,2]. The reperfusion, logical step in dealing with any situation of ischemia, is regarded as an important factor in the deterioration of the framework for local and systemic injury since predisposes to the formation of the so called reactive oxygen species that are responsible for direct tissue injury[4] This knowledge has led many researchers to search for a method capable of minimizing the damage caused during reperfusion, and highlights the use of some drugs for this purpose[5]. To evaluate the protective effect of postconditioning in hepatic ischemia and reperfusion process in rats

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