Ischemia-reperfusion histopathology alterations of the rabbit intestinal wall with and without exclusion of the collateral mesenteric circulation supply

Abstract

Purpose:To evaluate the histopathology alterations of the intestinal mucosa of rabbits submitted to different times of mesenteric artery ischemia and reperfusion with and without celiac artery collateral circulation supply. Methods: Two groups of eight male New Zealand white rabbits (weight 2.2-3.5 kg) were used in this study. In the Group 1 animals, the proximal mesenteric artery was occluded for 60 min with an atraumatic vascular clamp, followed by reperfusion for 60 min. In the Group 2 animals the small bowel and mesentery were cut 30cm and 60cm far from the gastroduodenal pyloric transition before the proximal mesenteric artery occlusion. Small bowel biopsies were obtained before ischemia (control), after 30 min and 60 min of mesenteric ischemia and at 30 and 60 min. of mesenteric artery reperfusion. Results: In the Group I animals, the followings histopathology grade results were observed: t1, mean 0.4 + 0.29; t2, mean 1.9 ± 0.38; t3, 1.9 ± 0.33; t4, 1.2 ± 0.36 and t5, 1.2 ± 0.32. Differences between t0 and t2 and between t3 and t4 were statistically significant (p<0.05). Differences between t2 and t3 and t4 and t5 were not significant (p>0.5). In the Group II animals, it was observed: t1, mean 1.6 ± 0.33; t2, 2.4 ± 0.36; t3, 3.0 ± 0.35; t4 3.4 ± 0.31; t5, 3 ± 031. Differences between t0 and t1, t1 and t2, and t2 and t3 were significant (p<0.05). Differences between histopathology grades results of samples t1 to t5 in Group 1 and 2 were statistically significant (p<0.5). Conclusion: Microscopic examination of the biopsies revealed significant evidence of worse small bowel wall ischemiareperfusion lesions by exclusion of the celiac artery collateral circulation supply. Key words: Mesenteric Vascular Occlusion. Vascular Diseases. Splanchnic Circulation. Rabbits. RESUMOObjetivo: Avaliar as alterações histopatológicas da mucosa intestinal de coelhos submetidos à isquemia-reperfusão com e sem exclusão da circulação mesentérica colateral. Métodos: Foram estudados dois grupos de oito coelhos Nova Zelândia machos com pesos variáveis entre 2,2 e 3,5 kg de peso corpóreo. Nos animais do Grupo 1, a artéria mesentérica proximal foi ocluida por pinçamento atraumático durante 60 min, seguido de reperfusão por 60 min. No Grupo 2 o intestino delgado e o mesentério foram seccionados 30 cm e 60 após a transição pilórica gastroduodenal antes da oclusão da artéria mesentérica cranial. Biópsias da parede intestinal foram obtidas antes da isquemia (controle), após 30 e 60 min. de isquemia. Resultados: No Grupo I foram observados os seguintes graus de lesões: t1,média de 0.4 + 0.29; t2, média 1.9 ± 0.38; t3, 1.9 ± 0.33; t4, 1.2 ± 0.36 e t5, 1.2 ± 0.32. As diferenças entre t0 e t2 e entre t3 e t4 foram significantes (p<0.05). As diferenças entre t2 e t3 e t4 e t5 não foram significantes (p>0.5). No Group II observou-se: t1, média de 1.6 ± 0.33; t2, 2.4 ± 0.36; t3, 3.0 ± 0.35; t4 3.4 ± 0.31; t5, 3 ± 031. As diferenças entre t0 e t1, t1 e t2, e t2 e t3 foram significantes (p<0.05). As diferenças entre os resultados histopato...

Brief topical and intraluminal use of Carolina rinse solution does not attenuate experimental ischemia and reperfusion injury in rabbit jejunum

“…In this study, integrity of the villi was preserved in group A ( Figure 1A). Detachment of enterocytes, lamina propria disintegration, and the presence of necrotic material were observed in groups B and C ( Figure 1B), as found in previous studies (Gomes et al, 2010;Gordeeva et al, 2015). After two hours of reperfusion (T120r), groups B and C showed similar shortening of the villus.…”

“…Previous studies have standardized the time of intestinal ischemia in rabbits ranging from one hour (Gomes et al, 2010) to two hours (Oliveira et al, 2018), in order to prevent irreversible tissue lesions. In this study, integrity of the villi was preserved in group A ( Figure 1A).…”

Ischemia-reperfusion histopathology alterations of the rabbit intestinal wall with and without ischemic preconditioning

“…In the present investigation ,considering the particular anatomy of the mesenteric circulation in rabbits, previously reported 24 , for mesenteric ischemia induction in all animals the small bowel and mesentery were cut 30cm and 60cm far from the gastroduodenal pyloric transition before the proximal mesenteric artery occlusion thus avoiding the interference of the collateral circulation from the gastroduodenal arterial supply .…”

“…The histopathology study was performed in the Pathology Anatomy Laboratory of the Minas Gerais Federal University School of Medicine and results described according to the following classification 7 , modified from Chiu, McArdle, Brown et al 8 classification in rats: Grade 0: Normal mucosa histology; Grade 1: Small cytology alterations in the cell structure representation. Increased leucocytes presence and space widening between villosities; Grade 2: Cell alterations with focused lesions and presence of some cell lysis.…”