Research Article: Effects of bradykinin preconditioning in an experimental intestinal ischemia reperfusion model on rats 1

Date Published: June 19, 2020

Publisher: Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia

Author(s): Fatih Dal, Can Küçük, Tutkun Talih, Erdoğan Sözüer, Uğur Topal, Kemal Deniz, Hızır Akyıldız.

http://doi.org/10.1590/s0102-865020200040000002

Abstract

To investigate the effects of bradykinin on reperfusion injury in an experimental intestinal ischemia reperfusion model.

We used 32 Wistar-Albino rats. We composed 4 groups each containing 8 rats. Rats in sham group were sacrified at 100 minutes observation after laparotomy. Thirty minutes reperfusion was performed following 50 minutes ischaemia in control group after observing 20 minutes. Ischaemic preconditioning was performed in one group of the study. We performed the other study group pharmacologic preconditioning by infusional administration of 10 μg/kg/minute bradykinin intravenously. We sacrified all of the rats by taking blood samples to evaluate the lactate and lactate dehydrogenase (LDH) after resection of jejunum for detecting tissue myeloperoxidase (MPO) activity.

Lactate and LDH levels were significantly higher in control and study groups than the sham group (P<0.001). There is no difference between the study groups statistically. (P>0.05). The results were the same for MPO levels. Although definitive cell damage was determinated in the control group by hystopatological evaluation, the damage in the study groups observed was lower in different levels. However, there was no significant difference between the study groups statistically (P>0.05).

Either ischeamic preconditioning or pharmacologic preconditioning made by bradykinin reduced the ischemia reperfusion injury at jejunum.

Partial Text

Restoring blood flow to ischemic tissue is essential for energy supply and cell survival. The most important condition to reduce the progression of ischemic damage is to minimize its duration, but through the reperfusion of ischemic tissues, a series of complex reactions that initiate tissue damage have already begun1 . Parks and Granger showed for the first time in 1983 that reperfusion damage was more severe than ischemic damage2 .

When LDH, Lactate and MPO values were compared, significantly lower levels were found between the sham group and the three other groups (p<0.001). The LDH, lactate and MPO levels were significantly lower in the IPC and PPC groups compared to the control group (p<0.001), and there was no significant difference between the PPC and IPC groups (p>0.05) ( Table 1 ).

IR damage is a complex process involving O2-derived free radicals, cytokines, NO and PMNLs7 . IR damage may occur in the intestinal system in cases of necrotizing enterocolitis, inflammatory bowel diseases, free pedicled bowel flap, cardiopulmonary bypass, strangulated hernia and bowel transplantation14 .

The potent vasodilator effect of BK may counterbalance vasoconstriction, a prominent mechanism in reperfusion injury. As a matter of fact, we achieved similar results with BK compared to IPC, which has previously proven efficacy in the small intestine.

 

Source:

http://doi.org/10.1590/s0102-865020200040000002

 

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