Postconditioning of the small intestine: which is the most effective algorithm in a rat model?
BACKGROUND
Mesenteric ischemia is a serious clinical condition requiring immediate surgical intervention. The unavoidable ischemic-reperfusion (IR) injury may be ameliorated using the appropriate postconditioning protocol. The aim of the present study was to investigate the optimal postconditioning algorithm in a rat model of intestinal ischemic-reperfusion injury.


METHODS
Male Wistar rats were randomized into five groups (n = 10), one sham-operated, one IR, and three postconditioned groups, each with different protocols. The animals were subjected to 60 min of mesenteric ischemia, followed by 60 min of reperfusion. Postconditioning was applied at the onset of reperfusion using three different algorithms. Arterial pressure and mucosal microcirculation were monitored throughout the experiment. Mesenteric pH was determined at the early phase of reperfusion. Blood and tissue samples were taken at the end of reperfusion for histologic evaluation, serum lactate dehydrogenase, serum creatine kinase, serum tumor necrosis factor-α, serum interleukin-6, detailed mucosal antioxidant, and scavenger capacity assays.


RESULTS
The shorter and intermediate length cycles of postconditioning enhanced mucosal microcirculation and redox state and significantly delayed the normalization of mesenteric pH. Furthermore, milder histopathologic lesions and lower concentrations of serum necroenzymes and proinflammatory cytokines were detected compared with the IR group. The protective effect of postconditioning using longer cycles could only be seen in a tendentious manner.


CONCLUSIONS
In a rat model of intestinal ischemia-reperfusion, the shorter and intermediate length cycles of postconditioning proved to be more effective than the use of longer cycles.
1st Department of Surgery, Semmelweis University, Budapest, Hungary. Electronic address: oliveross@gmail.com.
Oliver
O
Rosero
1st Department of Surgery, Semmelweis University, Budapest, Hungary.
Peter
P
Onody
1st Department of Surgery, Semmelweis University, Budapest, Hungary.
Rita
R
Stangl
1st Department of Surgery, Semmelweis University, Budapest, Hungary.
Zsolt
Z
Turoczi
1st Department of Surgery, Semmelweis University, Budapest, Hungary.
Andras
A
Fulop
1st Department of Surgery, Semmelweis University, Budapest, Hungary.
David
D
Garbaisz
2nd Department of Pathology, Semmelweis University, Budapest, Hungary.
Gabor
G
Lotz
1st Department of Surgery, Semmelweis University, Budapest, Hungary.
Laszlo
L
Harsanyi
1st Department of Surgery, Semmelweis University, Budapest, Hungary.
Attila
A
Szijarto
D000465:Algorithms; D000818:Animals; D003402:Creatine Kinase / Q000097:blood; D004195:Disease Models, Animal; D006439:Hemodynamics / Q000502:physiology; D007413:Intestinal Mucosa / Q000098:blood supply / Q000378:metabolism / Q000473:pathology; D007421:Intestine, Small / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D057775:Ischemic Postconditioning / Q000379:methods*; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008833:Microcirculation / Q000502:physiology; D011897:Random Allocation; D051381:Rats; D011920:Rats, Inbred WF; D015427:Reperfusion Injury / Q000378:metabolism / Q000601:surgery* / Q000628:therapy*; D013997:Time Factors
D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase
Intestinal ischemia; Mucosal microcirculation; Postconditioning algorithms; Rat; Reperfusion injury