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Bardell D, Rocchigiani G, Ressel L, Milner P. Histological Evaluation of Resected Tissue as a Predictor of Survival in Horses with Strangulating Small Intestinal Disease. Animals (Basel) 2023; 13:2715. [PMID: 37684979 PMCID: PMC10486948 DOI: 10.3390/ani13172715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/19/2023] [Accepted: 08/24/2023] [Indexed: 09/10/2023] Open
Abstract
Strangulating small intestinal disease (SSID) in horses carries a poor prognosis for survival, especially following resection of ischaemic tissue. The margins of a resection are principally based on visual appraisal of the intestine during surgery. We hypothesized that histological evaluation of resected tissue may identify occult changes indicative of prognosis. Small intestinal samples from 18 horses undergoing resection for SSID and 9 horses euthanised for reasons unrelated to gastrointestinal pathology were utilised. Histological appearance was used to generate a 'total damage score' (TDS) for the control tissue, grossly normal tissue at oral and aboral extremities (sections OR1 and AB1) of the resected intestine, and oral and aboral extremities of visually abnormal tissue (sections OR2 and AB2) from SSID horses. The relationship between TDS and long-term post-operative survival was investigated. TDS was not different between control tissues and OR1 and AB1 sections. Five surgical cases were alive at follow-up, the longest follow-up time being 2561 days. Based on the median scores for SSID cases versus controls, cut-off values were generated to evaluate post-operative survival versus TDS. Only OR2 TDS was significantly associated with survival, with a higher (worse) score indicating longer survival. More severe tissue insult may expedite rapid progression to surgery, improving post-operative outcomes.
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Affiliation(s)
- David Bardell
- Department of Equine Clinical Sciences, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK;
| | - Guido Rocchigiani
- Department of Veterinary Anatomy Physiology and Pathology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK; (G.R.); (L.R.)
| | - Lorenzo Ressel
- Department of Veterinary Anatomy Physiology and Pathology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK; (G.R.); (L.R.)
| | - Peter Milner
- Department of Equine Clinical Sciences, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK;
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Kilcoyne I. When Things Do Not Go As Planned: Update on Complications and Impact on Outcome. Vet Clin North Am Equine Pract 2023:S0749-0739(23)00014-7. [PMID: 37105780 DOI: 10.1016/j.cveq.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Affiliation(s)
- Isabelle Kilcoyne
- Department of Surgical and Radiological Sciences, UC Davis School of Veterinary Medicine, One Shields Avenue, Davis, CA 95616, USA.
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Verhaar N, de Buhr N, von Köckritz-Blickwede M, Dümmer K, Hewicker-Trautwein M, Pfarrer C, Dengler F, Kästner S. Hypoxia signaling in the equine small intestine: Expression and distribution of hypoxia inducible factors during experimental ischemia. Front Vet Sci 2023; 10:1110019. [PMID: 36908508 PMCID: PMC9998946 DOI: 10.3389/fvets.2023.1110019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 02/08/2023] [Indexed: 03/14/2023] Open
Abstract
Introduction Hypoxia inducible factors (HIF) are widely researched in human medicine for their role in different disease processes. The aim of this study was to investigate the expression and distribution of HIF in experimental small intestinal ischemia in the horse. Methods In 14 horses under general anesthesia, segmental jejunal ischemia with 90% reduction in blood flow was induced. The horses were randomly divided into two groups of seven horses, one subjected to ischemic postconditioning (IPoC) by delayed reperfusion, and a control group (group C) undergoing undelayed reperfusion. Intestinal samples were taken pre-ischemia, after ischemia and after reperfusion. Following immunohistochemical staining for HIF1α and -2α, the immunoreactivity pattern in the small intestine was evaluated by light microscopy, and the mucosal enterocyte and muscularis staining were semi-quantitatively scored. Additionally, mucosal HIF1α protein levels were determined by an Enzyme Linked Immunosorbent Assay (ELISA), and mRNA levels of HIF1α and its target genes by a two-step real-time Reverse Transcriptase Polymerase Chain Reaction. Statistical comparison was performed between the groups and time points using parametric and non-parametric tests (p < 0.05). Results All cell types exhibited cytoplasmic and nuclear immunoreactivity for HIF1α. After reperfusion, the cytoplasmic staining of the crypt and villus enterocytes as well as the villus nuclear staining significantly increased, whereas the perinuclear granules in the crypts decreased. The protein levels showed a significant decrease in group C at reperfusion, with lower HIF1α levels in group C compared to group IPoC during ischemia and reperfusion. No other group differences could be detected. In the HIF2α stained slides, mild to moderate cytoplasmic staining yet no nuclear immunoreactivity of the enterocytes was observed, and no significant changes over time were noted. Discussion the changes in HIF1α immunoreactivity pattern and expression over time suggest that this transcription factor plays a role in the intestinal response to ischemia in horses. However, the current study could not identify an effect of IPoC on HIF distribution or expression.
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Affiliation(s)
- Nicole Verhaar
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Nicole de Buhr
- Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany.,Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Maren von Köckritz-Blickwede
- Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany.,Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Katrin Dümmer
- Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany.,Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Hannover, Germany
| | | | - Christiane Pfarrer
- Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Franziska Dengler
- Institute of Physiology, Pathophysiology and Biophysics, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Sabine Kästner
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.,Small Animal Clinic, University of Veterinary Medicine Hannover, Hannover, Germany
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Dengler F, Sternberg F, Grages M, Kästner SBR, Verhaar N. Adaptive mechanisms in no flow vs. low flow ischemia in equine jejunum epithelium: Different paths to the same destination. Front Vet Sci 2022; 9:947482. [PMID: 36157182 PMCID: PMC9493374 DOI: 10.3389/fvets.2022.947482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/17/2022] [Indexed: 01/18/2023] Open
Abstract
Intestinal ischemia reperfusion injury (IRI) is a frequent complication of equine colic. Several mechanisms may be involved in adaptation of the intestinal epithelium to IRI and might infer therapeutic potential, including hypoxia-inducible factor (HIF) 1α, AMP-activated protein kinase (AMPK), nuclear factor-erythroid 2-related factor 2 (NRF2), and induction of autophagy. However, the mechanisms supporting adaptation and thus cellular survival are not completely understood yet. We investigated the activation of specific adaptation mechanisms in both no and low flow ischemia and reperfusion simulated in equine jejunum epithelium in vivo. We found an activation of HIF1α in no and low flow ischemia as indicated by increased levels of HIF1α target genes and phosphorylation of AMPKα tended to increase during ischemia. Furthermore, the protein expression of the autophagy marker LC3B in combination with decreased expression of nuclear-encoded mitochondrial genes indicates an increased rate of mitophagy in equine intestinal IRI, possibly preventing damage by mitochondria-derived reactive oxygen species (ROS). Interestingly, ROS levels were increased only shortly after the onset of low flow ischemia, which may be explained by an increased antioxidative defense, although NFR2 was not activated in this setup. In conclusion, we could demonstrate that a variety of adaptation mechanisms manipulating different aspects of cellular homeostasis are activated in IRI irrespective of the ischemia model, and that mitophagy might be an important factor for epithelial survival following small intestinal ischemia in horses that should be investigated further.
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Affiliation(s)
- Franziska Dengler
- Department of Biochemical Sciences, Institute of Physiology, Pathophysiology and Biophysics, University of Veterinary Medicine, Vienna, Austria
- *Correspondence: Franziska Dengler
| | - Felix Sternberg
- Department of Biochemical Sciences, Institute of Physiology, Pathophysiology and Biophysics, University of Veterinary Medicine, Vienna, Austria
| | - Marei Grages
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Sabine BR Kästner
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
- Small Animal Clinic, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Nicole Verhaar
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
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Low Flow versus No Flow: Ischaemia Reperfusion Injury Following Different Experimental Models in the Equine Small Intestine. Animals (Basel) 2022; 12:ani12162158. [PMID: 36009747 PMCID: PMC9405230 DOI: 10.3390/ani12162158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/17/2022] [Accepted: 08/19/2022] [Indexed: 11/17/2022] Open
Abstract
Simple Summary One of the main causes of colic in horses is the occlusion of the intestinal blood vessels after displacement or entrapment of the small intestine. In search of new therapies to treat this lethal disease, experimental models have been used to simulate the clinical situation. Both low flow (LF) models with partial blood flow occlusion as well as no flow (NF) models with complete occlusion have been implemented in different studies. This has led to conflicting results and comparative studies are lacking. The objective of this study was to characterize the development of intestinal injury over time in two different experimental models implementing either partial or complete vessel occlusion. Under general anaesthesia, local intestinal blood flow was reduced by 80% in seven horses (LF), and by 100% in another seven horses (NF). The LF group exhibited more bleeding in the intestinal wall and a relatively high variability in intestinal oxygen levels and tissue damage. The NF group showed lower oxygen levels and decreased barrier function of the intestinal wall. These results aid in the selection of the suitable experimental model for future studies. The high variability following LF suggests that an NF model may produce more consistent intestinal damage. Abstract In experimental studies investigating strangulating intestinal lesions in horses, different ischaemia models have been used with diverging results. Therefore, the aim was to comparatively describe ischaemia reperfusion injury (IRI) in a low flow (LF) and no flow (NF) model. Under general anaesthesia, 120 min of jejunal ischaemia followed by 120 min of reperfusion was induced in 14 warmbloods. During ischaemia, blood flow was reduced by 80% (LF, n = 7) or by 100% (NF, n = 7). Intestinal blood flow and oxygen saturation were measured by Laser Doppler fluxmetry and spectrophotometry. Clinical, histological, immunohistochemical and Ussing chamber analyses were performed on intestinal samples collected hourly. Tissue oxygen saturation was significantly lower in NF ischaemia. The LF group exhibited high variability in oxygen saturation and mucosal damage. Histologically, more haemorrhage was found in the LF group at all time points. Cleaved-caspase-3 and calprotectin-stained cells increased during reperfusion in both groups. After NF ischaemia, the tissue conductance was significantly higher during reperfusion. These results aid in the selection of suitable experimental models for future studies. Although the LF model has been suggested to be more representative for clinical strangulating small intestinal disease, the NF model produced more consistent IRI.
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Bowlby C, Mudge M, Schroeder E, Godman J, Hurcombe S. Equine inflammatory response to abdominal surgery in the absence of gastrointestinal disease. J Vet Emerg Crit Care (San Antonio) 2021; 31:601-607. [PMID: 34196457 DOI: 10.1111/vec.13092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 12/25/2019] [Accepted: 01/15/2020] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To investigate the, equine inflammatory response to ventral midline celiotomy in the absence of gastrointestinal disease in horses of varying body condition scores primarily using serial measurements of serum amyloid A (SAA). DESIGN Experimental clinical study. SETTING University teaching hospital. ANIMALS Ten adult light breed horses free of any clinical disease, 5 with body condition score (BCS) 3-4/9 and 5 with BCS 7-8/9. INTERVENTIONS Horses had a ventral midline celiotomy performed under general anesthesia, including manual decompression of the small intestine. SAA, semiquantitative fibrinogen, plasma lactate, and WBC count were measured in the blood preoperatively and at 12, 24, 48, 72, 120, and 168 hours postoperatively. Complete serum biochemistry was performed preoperatively and 24 and 72 hours postoperatively. Serial abdominocentesis was also performed with peritoneal fluid analysis of SAA, total protein, lactate, WBC count, and cytology. MEASUREMENTS AND MAIN RESULTS Significant (P < 0.05) increases in serum SAA were noted at 12, 24, and 48 hours postoperatively (124.6 ± 68.6, 390.8 ± 209.0, 568.6 ± 197.7 μg/mL), and most horses had values approaching normal at 168 hours postoperatively (174.4 ± 307.7 μg/mL). Other values such as fibrinogen also increased in response to surgery but did not return to normal within the measured time points. Horses with high BCS did not have significantly different serum SAA compared to horses with low BCS. Peritoneal fluid SAA did not increase significantly at 12 hours postoperatively. CONCLUSIONS The information from this study can be used to help determine the effect of anesthesia and surgical intestinal manipulation resulting in increased SAA when a comparison to clinical or experimental cases is needed.
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Affiliation(s)
- Charles Bowlby
- Department of Animal Sciences, The Ohio State University, Columbus, Ohio, USA
| | - Margaret Mudge
- Department of Clinical Sciences, The Ohio State University, Columbus, Ohio, USA
| | - Eric Schroeder
- Department of Clinical Sciences, The Ohio State University, Columbus, Ohio, USA
| | - Jennifer Godman
- Department of Clinical Sciences, The Ohio State University, Columbus, Ohio, USA
| | - Samuel Hurcombe
- Department of Clinical Studies, University of Pennsylvania Kennett Square, Pennsylvania, USA
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Verhaar N, de Buhr N, von Köckritz-Blickwede M, Hewicker-Trautwein M, Pfarrer C, Mazzuoli-Weber G, Schulte H, Kästner S. Ischaemic postconditioning reduces apoptosis in experimental jejunal ischaemia in horses. BMC Vet Res 2021; 17:175. [PMID: 33902575 PMCID: PMC8077964 DOI: 10.1186/s12917-021-02877-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 04/12/2021] [Indexed: 03/06/2023] Open
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.
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Affiliation(s)
- Nicole Verhaar
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.
| | - Nicole de Buhr
- Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Maren von Köckritz-Blickwede
- Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Hannover, Germany
| | | | - Christiane Pfarrer
- Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Gemma Mazzuoli-Weber
- Institute for Physiology and Cell Biology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Henri Schulte
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Sabine Kästner
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
- Small Animal Clinic, University of Veterinary Medicine Hannover, Hannover, Germany
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VanderBroek AR, Engiles JB, Kästner SBR, Kopp V, Verhaar N, Hopster K. Protective effects of dexmedetomidine on small intestinal ischaemia-reperfusion injury in horses. Equine Vet J 2020; 53:569-578. [PMID: 32862437 DOI: 10.1111/evj.13337] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 07/06/2020] [Accepted: 08/13/2020] [Indexed: 12/26/2022]
Abstract
BACKGROUND Strangulating small intestinal lesions in the horse have increased morbidity and mortality compared to nonstrangulating obstructions due to mucosal barrier disruption and subsequent endotoxaemia. OBJECTIVES To investigate protective effects of dexmedetomidine on small intestinal ischaemia-reperfusion injury in the horse. STUDY DESIGN Randomised, controlled, experimental study. METHODS Eighteen systemically healthy horses were randomly assigned to three groups: control, preconditioning, and post-conditioning. During isoflurane anaesthesia, complete ischaemia was induced in a 1-m segment of jejunum for 90 minutes. Horses in the preconditioning and post-conditioning groups received dexmedetomidine (3.5 µg/kg followed by 7 µg/kg/h) before (preconditioning) or after beginning ischaemia (post-conditioning), and during reperfusion. Jejunal biopsies were collected before ischaemia (baseline-1), at the end of the ischaemic period (ischaemia), and 30 minutes after reperfusion (reperfusion-1). Additional biopsies were taken 24 hours after reperfusion from ischaemia-reperfusion-injured jejunum (reperfusion-2). Epithelial injury was scored histologically, and morphometric analyses were used to calculate villus surface area (VSA) denuded of epithelium. Data were analysed using analysis of variance, Kruskal-Wallis and Wilcoxon two-sample tests. RESULTS In the control group, epithelial injury scores and percentage of VSA denudation for ischaemia-reperfusion-injured jejunum were higher compared to baseline-1 at all time points. The ischaemia and both reperfusion samples from the pre- and post-conditioning groups had lower epithelial injury scores and percentage of VSA epithelial denudation compared to the control group, with no difference from baseline-1 at any time point for the preconditioning group. MAIN LIMITATIONS Preconditioning has limited application in the clinical setting with naturally occurring strangulating small intestinal lesions. CONCLUSIONS Dexmedetomidine was protective for small intestinal ischaemia-reperfusion injury in the horse when administered before or during ischaemia.
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Affiliation(s)
- Ashley R VanderBroek
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
| | - Julie B Engiles
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA, USA
| | - Sabine B R Kästner
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Veronika Kopp
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Nicole Verhaar
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Klaus Hopster
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA, USA
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Verhaar N, Pfarrer C, Neudeck S, König K, Rohn K, Twele L, Kästner S. Preconditioning with lidocaine and xylazine in experimental equine jejunal ischaemia. Equine Vet J 2020; 53:125-133. [PMID: 32119148 DOI: 10.1111/evj.13251] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 12/17/2019] [Accepted: 02/20/2020] [Indexed: 01/01/2023]
Abstract
BACKGROUND Pharmacological preconditioning of dexmedetomidine on small intestinal ischaemia/reperfusion injury has been reported in different animal models including horses. OBJECTIVES The objective was to assess if xylazine and lidocaine have a preconditioning effect in an experimental model of equine jejunal ischaemia. STUDY DESIGN Terminal in vivo experiment. METHODS Ten horses under general anaesthesia were either preconditioned with xylazine (group X; n = 5) or lidocaine (group L; n = 5). A historical untreated control group (group C; n = 5) was used for comparison. An established experimental model of equine jejunal ischaemia was applied, and intestinal samples were taken pre-ischaemia, after ischaemia and following reperfusion. Histomorphological examination was performed based on a modified Chiu score. Immunohistochemical staining for cleaved caspase-3, TUNEL and calprotectin was performed, and positive cell counts were expressed in cells/mm2 . RESULTS There was no progression of histomorphological mucosal injury from ischaemia to reperfusion, and there were no differences in histomorphology between the groups. After ischaemia, group X had significantly less caspase-positive cells compared to the control group with a median difference of 227% (P = .01). After reperfusion, group X exhibited significantly lower calprotectin-positive cell counts compared to the control group, with a median difference of 6.8 cells/mm2 in the mucosa and 44 cells in the serosa (P = .02 and .05 respectively). All groups showed an increase in caspase- and calprotectin-positive cells during reperfusion (P < .05). TUNEL-positive cells increased during ischaemia, followed by a decrease after reperfusion (P < .05). MAIN LIMITATIONS The small sample size and the use of a historical control group. Preconditioning effects of the tested drugs may be masked by the protective effects of isoflurane in the anaesthetic protocol. CONCLUSIONS Preconditioning with lidocaine did not have any effect on the tested variables. The lower cell counts of caspase- and calprotectin-positive cells in group X may indicate a beneficial effect of xylazine on ischaemia/reperfusion injury. Due to the absence of a concurrent reduction of histomorphological injury, the clinical significance remains uncertain.
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Affiliation(s)
- Nicole Verhaar
- Clinic for Horses, University of Veterinary Medicine, Hannover, Germany
| | - Christiane Pfarrer
- Institute for Anatomy, University of Veterinary Medicine, Hannover, Germany
| | - Stephan Neudeck
- Clinic for Horses, University of Veterinary Medicine, Hannover, Germany
| | - Kathrin König
- Clinic for Horses, University of Veterinary Medicine, Hannover, Germany
| | - Karl Rohn
- Department of Biometry, University of Veterinary Medicine, Hannover, Germany
| | - Lara Twele
- Clinic for Horses, University of Veterinary Medicine, Hannover, Germany
| | - Sabine Kästner
- Clinic for Horses, University of Veterinary Medicine, Hannover, Germany
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10
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Freeman DE. Letter to the Editor: Response to Dr Blikslager's letter on post‐operative reflux. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D. E. Freeman
- Department of Large Animal Clinical Sciences College of Veterinary Medicine University of Florida Gainesville Florida USA
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11
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Kopper JJ, Travers JL, Schott HC, Cook VL. Effect of body condition on intestinal permeability in horses. Am J Vet Res 2019; 80:792-798. [PMID: 31339765 DOI: 10.2460/ajvr.80.8.792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To investigate effects of body condition on permeability of intestinal mucosa in horses. ANIMALS 13 horses (7 obese and 6 lean) from 8 to 15 years of age. PROCEDURES Body condition score was assessed, and an oral sugar test (OST) was performed to evaluate glucose and insulin dynamics. Horses were allowed a 2-week diet acclimation period and were then euthanized. Tissue samples were collected from the jejunum, ileum, cecum, pelvic flexure, right dorsal colon, and rectum. Mucosal permeability was assessed by measuring transepithelial resistance and lipopolysaccharide (LPS) flux across tissue samples mounted in Ussing chambers. RESULTS 5 obese horses and 1 lean horse had evidence of insulin dysregulation, whereas 1 obese and 5 lean horses had no abnormalities in results of the OST. Results for the OST were not available for 1 obese horse. Mucosal transepithelial resistance did not differ in any intestinal segment between obese and lean horses. Obese horses had a significantly higher LPS flux across jejunal mucosa, compared with results for lean horses, but there were no significant differences between obese and lean horses for other intestinal segments. CONCLUSIONS AND CLINICAL RELEVANCE Obese horses may have had greater paracellular mucosal permeability of jejunal mucosa to LPS, compared with that for lean horses. This finding was consistent with data for the gastrointestinal mucosa of humans and mice and supported the hypothesis that obese horses may be at higher risk from chronic exposure to increased amounts of LPS, compared with the risk for lean horses.
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Freeman DE. Is There Still a Place for Lidocaine in the (Postoperative) Management of Colics? Vet Clin North Am Equine Pract 2019; 35:275-288. [PMID: 31076222 DOI: 10.1016/j.cveq.2019.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Intravenous lidocaine is widely used to prevent or treat postoperative ileus in horses. Clinical studies that support this approach are flawed and contradicted by others. Also, physical obstruction could be more important in causing postoperative reflux than postoperative ileus in the horse. The antiinflammatory properties of lidocaine and the role of inflammation from intestinal handling in the genesis of postoperative reflux are questionable. Because of cost and questionable efficacy of lidocaine, a well-designed clinical trial is required to support its continued use. However, lidocaine could be given to provide or enhance analgesia in selected cases with postoperative colic.
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Affiliation(s)
- David E Freeman
- Equine Surgery, University of Florida, College of Veterinary Medicine, Large Animal Clinical Sciences, PO Box 100136, Gainesville, FL 32610, USA.
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13
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Freeman DE. Fifty years of colic surgery. Equine Vet J 2018; 50:423-435. [DOI: 10.1111/evj.12817] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 12/05/2017] [Accepted: 01/10/2018] [Indexed: 12/21/2022]
Affiliation(s)
- D. E. Freeman
- Department of Large Animal Clinical Sciences; College of Veterinary Medicine; University of Florida; Gainesville Florida USA
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Anderson SL, Singh B. Equine neutrophils and their role in ischemia reperfusion injury and lung inflammation. Cell Tissue Res 2018; 371:639-648. [PMID: 29335779 DOI: 10.1007/s00441-017-2770-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 12/07/2017] [Indexed: 01/06/2023]
Abstract
Horses are susceptible to a multitude of inflammatory conditions that are characterized by a strong neutrophilic response. Here, we review basic equine neutrophil biology and explore the role of neutrophils in inflammatory conditions with emphasis on intestinal ischemia and reperfusion injury and lung inflammation. In addition, unique aspects of equine neutrophil biology have been highlighted. Neutrophils comprise the highest proportion of circulating white blood cells in equine blood. The concentration of circulating equine neutrophils is a primary indicator of systemic inflammation. Additionally, equine neutrophils exposed to various stimulants develop "toxic" changes characterized as cytoplasmic basophilia, presence of Döhle bodies, cytoplasmic vacuolation and toxic granulation. In contrast to human neutrophils, equine neutrophils fail to undergo chemotaxis in response to the peptide N-formyl-methionyl-leucyl-phenylalanine and are dependent on the addition of arachidonic acid due to reduced activity of phospholipase A2 to synthesize leukotrienes as part of the arachidonic acid pathway. Understanding the biologic function of neutrophils in horses is integral to developing methods to modulate inflammation associated with ischemia reperfusion injury and lung disease.
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Affiliation(s)
- Stacy L Anderson
- College of Veterinary Medicine, Lincoln Memorial University, 6965 Cumberland Gap Parkway, Harrogate, TN, 37752, USA.
| | - Baljit Singh
- College of Veterinary Medicine, University of Calgary, Calgary, Alberta, T2N 4Z6, Canada
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