Nicole Verhaar1, Nicole de Buhr2,3, Maren von Köckritz-Blickwede2,3, Marion Hewicker-Trautwein4, Christiane Pfarrer5, Gemma Mazzuoli-Weber6, Henri Schulte7, Sabine Kästner8,9. 1. Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany. nicole.verhaar@tiho-hannover.de. 2. Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany. 3. Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Hannover, Germany. 4. Institute of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany. 5. Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany. 6. Institute for Physiology and Cell Biology, University of Veterinary Medicine Hannover, Hannover, Germany. 7. Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany. 8. Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany. 9. Small Animal Clinic, University of Veterinary Medicine Hannover, Hannover, Germany.
Abstract
BACKGROUND: Ischaemic postconditioning (IPoC) refers to brief periods of reocclusion of blood supply following an ischaemic event. This has been shown to ameliorate ischaemia reperfusion injury in different tissues, and it may represent a feasible therapeutic strategy for ischaemia reperfusion injury following strangulating small intestinal lesions in horses. The objective of this study was to assess the degree cell death, inflammation, oxidative stress, and heat shock response in an equine experimental jejunal ischaemia model with and without IPoC. METHODS: In this randomized, controlled, experimental in vivo study, 14 horses were evenly assigned to a control group and a group subjected to IPoC. Under general anaesthesia, segmental ischaemia with arterial and venous occlusion was induced in 1.5 m jejunum. Following ischaemia, the mesenteric vessels were repeatedly re-occluded in group IPoC only. Full thickness intestinal samples and blood samples were taken at the end of the pre-ischaemia period, after ischaemia, and after 120 min of reperfusion. Immunohistochemical staining or enzymatic assays were performed to determine the selected variables. RESULTS: The mucosal cleaved-caspase-3 and TUNEL cell counts were significantly increased after reperfusion in the control group only. The cleaved-caspase-3 cell count was significantly lower in group IPoC after reperfusion compared to the control group. After reperfusion, the tissue myeloperoxidase activity and the calprotectin positive cell counts in the mucosa were increased in both groups, and only group IPoC showed a significant increase in the serosa. Tissue malondialdehyde and superoxide dismutase as well as blood lactate levels showed significant progression during ischaemia or reperfusion. The nuclear immunoreactivity of Heat shock protein-70 increased significantly during reperfusion. None of these variables differed between the groups. The neuronal cell counts in the myenteric plexus ganglia were not affected by the ischaemia model. CONCLUSIONS: A reduced apoptotic cell count was found in the group subjected to IPoC. None of the other tested variables were significantly affected by IPoC. Therefore, the clinical relevance and possible protective mechanism of IPoC in equine intestinal ischaemia remains unclear. Further research on the mechanism of action and its effect in clinical cases of strangulating colic is needed.
BACKGROUND: Ischaemic postconditioning (IPoC) refers to brief periods of reocclusion of blood supply following an ischaemic event. This has been shown to ameliorate ischaemia reperfusion injury in different tissues, and it may represent a feasible therapeutic strategy for ischaemia reperfusion injury following strangulating small intestinal lesions in horses. The objective of this study was to assess the degree cell death, inflammation, oxidative stress, and heat shock response in an equine experimental jejunal ischaemia model with and without IPoC. METHODS: In this randomized, controlled, experimental in vivo study, 14 horses were evenly assigned to a control group and a group subjected to IPoC. Under general anaesthesia, segmental ischaemia with arterial and venous occlusion was induced in 1.5 m jejunum. Following ischaemia, the mesenteric vessels were repeatedly re-occluded in group IPoC only. Full thickness intestinal samples and blood samples were taken at the end of the pre-ischaemia period, after ischaemia, and after 120 min of reperfusion. Immunohistochemical staining or enzymatic assays were performed to determine the selected variables. RESULTS: The mucosal cleaved-caspase-3 and TUNEL cell counts were significantly increased after reperfusion in the control group only. The cleaved-caspase-3 cell count was significantly lower in group IPoC after reperfusion compared to the control group. After reperfusion, the tissue myeloperoxidase activity and the calprotectin positive cell counts in the mucosa were increased in both groups, and only group IPoC showed a significant increase in the serosa. Tissue malondialdehyde and superoxide dismutase as well as blood lactate levels showed significant progression during ischaemia or reperfusion. The nuclear immunoreactivity of Heat shock protein-70 increased significantly during reperfusion. None of these variables differed between the groups. The neuronal cell counts in the myenteric plexus ganglia were not affected by the ischaemia model. CONCLUSIONS: A reduced apoptotic cell count was found in the group subjected to IPoC. None of the other tested variables were significantly affected by IPoC. Therefore, the clinical relevance and possible protective mechanism of IPoC in equineintestinal ischaemia remains unclear. Further research on the mechanism of action and its effect in clinical cases of strangulating colic is needed.
Authors: Andreas Türler; Jörg C Kalff; Beverley A Moore; Rosemary A Hoffman; Timothy R Billiar; Richard L Simmons; Anthony J Bauer Journal: Ann Surg Date: 2006-08 Impact factor: 12.969
Authors: N J Vatistas; J R Snyder; S V Hildebrand; F A Harmon; M J Woliner; S J Barry; J Nieto; P Henry; L R Enos; D Magliano; S A Brown; C Drake Journal: Am J Vet Res Date: 1996-05 Impact factor: 1.156