Name: demonstration of the rat ischemic skin wound model
Uploaded: 2015-04-01T15:00:00
Description: Watch this Scientific Journal Video about Demonstration of the Rat Ischemic Skin Wound Model at JoVE.com

The authors would like to acknowledge funding support from the University of South Florida, Department of Surgery (Mack Wu, MD, PhD).

BEMÆRK: Godkendelse af alle dyreforsøg præsenteres nedenfor blev opnået fra University of South Florida Animal Care Udvalg (IACUC) og overholde alle krav i dyreværnsloven og vejledningen for pasning og anvendelse af forsøgsdyr. 1. Fremstilling af silikone Plader og kirurgiske instrumenter <ol><li> Forskåret strimler (10,5 cm x 3,0 cm) af ikke-forstærket 0,01 tykkelse, medicinsk silikone presenningen og sterilisere ved hjælp af en autoklave. </li><li> Rens og sterilisere egnede kir...

<ol>
	<li>Ansell, D. M., Holden, K. A., Hardman, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+of+wound+repair:+Are+they+cutting+it.">Animal models of wound repair: Are they cutting it.</a> Experimental dermatology. 21 (8), 581-585 (2012).</li><li>Dorsett-Martin, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rat+models+of+skin+wound+healing:+a+review.">Rat models of skin wound healing: a review.</a> Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society. 12 (6), 591-599 (2003).</li><li>Davidson, J. 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J., Leong, M., Sonstein, J., Wilson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimization+and+validation+of+an+ischemic+wound+model.">Optimization and validation of an ischemic wound model.</a> Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society. 13 (6), 576-582 (2004).</li><li>Loots, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differences+in+cellular+infiltrate+and+extracellular+matrix+of+chronic+diabetic+and+venous+ulcers+versus+acute+wounds.">Differences in cellular infiltrate and extracellular matrix of chronic diabetic and venous ulcers versus acute wounds.</a> The Journal of investigative dermatology. 111 (5), 850-857 (1998).</li><li>Schwartz, D. A., Lindblad, W. J., Rees, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Altered+collagen+metabolism+and+delayed+healing+in+a+novel+model+of+ischemic+wounds.">Altered collagen metabolism and delayed healing in a novel model of ischemic wounds.</a> Wound Repair Regen. 3 (2), 204-212 (1995).</li><li>Chen, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+and+mechanistic+validation+of+delayed+healing+rat+wounds+as+a+model+for+human+chronic+wounds.">Molecular and mechanistic validation of delayed healing rat wounds as a model for human chronic wounds.</a> Wound Repair and Regeneration. 7, (1999).</li><li>Zhang, Q., Chang, Q., Cox, R. A., Gong, X., Gould, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperbaric+oxygen+attenuates+apoptosis+and+decreases+inflammation+in+an+ischemic+wound+model.">Hyperbaric oxygen attenuates apoptosis and decreases inflammation in an ischemic wound model.</a> The Journal of investigative dermatology. 128 (8), 2102-2112 (2008).</li><li>Zhang, Q., Gould, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyperbaric+oxygen+reduces+matrix+metalloproteinases+in+ischemic+wounds+through+a+redox-dependent+mechanism.">Hyperbaric oxygen reduces matrix metalloproteinases in ischemic wounds through a redox-dependent mechanism.</a> The Journal of investigative dermatology. 134 (1), 237-246 (2013).</li><li>Moor, A. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Consequences+of+age+on+ischemic+wound+healing+in+rats:+altered+antioxidant+activity+and+delayed+wound+closure.">Consequences of age on ischemic wound healing in rats: altered antioxidant activity and delayed wound closure.</a> Age (Dordrecht, Netherlands). 36 (2), 733-748 (2014).</li><li>Roy, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+a+preclinical+model+of+chronic+ischemic+wound).">Characterization of a preclinical model of chronic ischemic wound).</a> Physiological genomics. 37 (3), 211-224 (2009).</li><li>Biswas, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypoxia+inducible+microRNA+210+attenuates+keratinocyte+proliferation+and+impairs+closure+in+a+murine+model+of+ischemic+wounds.">Hypoxia inducible microRNA 210 attenuates keratinocyte proliferation and impairs closure in a murine model of ischemic wounds.</a> Proceedings of the National Academy of Sciences of the United States of America. 107 (15), 6976-6981 (2010).</li><li>Winocour, S., Vorstenbosch, J., Trzeciak, A., Lessard, L., Philip, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD109,+a+novel+TGF-beta+antagonist,+decreases+fibrotic+responses+in+a+hypoxic+wound+model.">CD109, a novel TGF-beta antagonist, decreases fibrotic responses in a hypoxic wound model.</a> Exp Dermatol. 23 (7), 475-479 (2014).</li></ol>

<html> Sårheling hos rotter har ofte været genstand for debat på grund af deres evne til at helbrede inficerede sår og høje interanimal variabilitet 5. En af de oprindelige mål af modellen under udviklingen var at mindske denne variation. Ændringer i bredden af ​​klappen, hvilket reducerer antallet af sår med specifik placering (centreret på flappen med konsekvent kranio-caudale placering) og indførelse af et silicone ark har opnået dette mål. Sårheling ved sammentrækning er også blevet redu...

Effektiv lægemiddeludvikling og andre sårhelende lægemidler kræver passende in vivo modeller, på trods af kendte problemer med at oversætte fund i dyremodeller for humane terapier 1. Det følgende er en beskrivelse af en detaljeret protokol for anvendelse af en rottemodel for iskæmisk hud sårheling at undersøge mekanismer, der yderligere forståelse af patologiske sårheling. De rotte arter, ofte er ansat på grund af sin brede tilgængelighed, størrelse og føjelig naturen bruges til sårheling undersøgelser, da det er stort nok til at give et passende hudområde til incisional og excisional såret, billedbehandling og væv kollektion 2. Det skal dog tages i nøje overvejelse, at huden på en rotte og en menneskelig er forskellige anatomisk, med rotter benævnes løs-flået dyr. Denne særskilte egenskab giver mulighed for sår sammentrækning, snarere end epitelialisering at bidrage væsentligt til lukning af rottehud wounds 2. Derudover er tilstedeværelsen af en subkutan panniculus carnosus muskulatur i rotter, bidrager til heling af både kontraktion og kollagen formation 3,4. Disse meget vigtige anatomiske forskelle blev anset for udviklingen af rotte iskæmisk hudsår model og specifikke modifikationer blev gennemført for at mindske sår sammentrækning og reducere indflydelsen af panniculus carnosus muskulatur 5. Hos diabetiske fodsår, venøse bensår og tryksår, er healing forsinket, og disse sår betragtes kronisk. Sårene er kendetegnet ved overdreven inflammation, som forhindrer såret udvikler sig og de ​​næste faser i sårheling 6. En af de vigtigste faktorer i udviklingen af en kronisk sår er lokaliseret væv iskæmi (reduceret blodstrømning) 5 bidrager til den manglende evne til at fjerne betændelse. På det tidspunkt, hvor denne model blev udviklet og valideret (i 2003-4), Var der ingen standardiserede dyremodeller, der kunne give nok væv til at teste induktion af angiogenese i såret, et afgørende tidspunkt under normal sårheling og motivationen for at udvikle denne model 5. Det er sagt, model præsenteres her er en modifikation af den iskæmiske sår model oprindeligt beskrevet af Schwartz et al. 7 og efterfølgende anvendes i modificeret form af Chen et al. 8 I den modificerede iskæmisk sår model er der foretaget ændringer for at omgå de ovenfor nævnte anatomiske karakteristika af rotte, der fører til helbredelse ved sammentrækning stedet epitelialisering: (1) To fuld tykkelse Excisionssår er skabt inden for en bipedicled flap dorsale hud og panniculus carnosus muskulatur fjernes fra såret ved dissekering lige over muskelfascie. (2) flap selv har mere smalle dimensioner, der sikrer, at blodforsyningen er tilfældig og sår placeret ved midtpunktet af than klap er iskæmisk. (3) En silicone ark indsættes under klappen, forebygge readherence og reperfusion af klappen fra det underliggende væv. Sår sammentrækning er begrænset (ikke elimineres) ved at forankre eller suturering klappen til silikone ark 5. Modellen er for nylig blevet anvendt i undersøgelser spænder fra oxygenovertrykskramper virkninger på iskæmisk sårheling 9,10 til iskæmisk sårheling hos unge versus ældre rotter 11 og har vist sig at være en pålidelig model for langvarig vævsiskæmi. Dimensionerne af bipedicled flap er også blevet tilpasset til forskellige rottestammer, herunder Sprague Dawley (11 cm lang og 2 cm bred) og F344-rotter (10,5 cm lang med 3,0-3,5 cm bred) og andre arter, herunder svin 12 og mus 13,14. Denne video udnytter F344 indavlede rotte stamme i demonstrationen af ​​den iskæmiske hudsår model. Godkendelse af alle dyreforsøg præsenteres nedenfor var fåed fra University of South Florida Animal Care Udvalg (IACUC) og overholde alle krav i dyreværnsloven og vejledningen for pleje og anvendelse af forsøgsdyr.

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demonstration of the rat ischemic skin wound model

Tilbøjeligheden til kroniske sår hos mennesker stiger med aldring, sygdomstilstande såsom diabetes og nedsat kardiovaskulær funktion og unrelieved pres på grund af immobilitet. Animal modeller er blevet udviklet, forsøg på at efterligne disse forhold med henblik på at fremme vores forståelse af kompleksiteten af ​​kroniske sår. Den beskrevne model er en rotte iskæmisk hudlap model, der tillader en forlænget reduktion af blodstrømmen resulterer i sår, der bliver iskæmisk og ligner et kronisk sår fænotype (reduceret vaskularisering, øget inflammation og forsinket sårlukning). Den består af en bipedicled dorsal klap med 2 iskæmiske sår placeret centralt og 2 ikke-iskæmiske sår lateralt i forhold til klappen som kontroller. En ny tilføjelse til dette iskæmisk hudlap model er placeringen af ​​en silikone ark under klappen, der fungerer som en barriere og en skinne for at forhindre revaskularisering og mindske sammentrækning som sår heles. Trodsdebat anvendelse rotter til sårheling undersøgelser på grund af deres helt forskellige anatomiske og fysiologiske forskelle i forhold til mennesker (dvs. tilstedeværelsen af en panniculus carnosus muskulatur, kort levetid, øget antal hårsække, og deres evne til at helbrede inficerede sår) ændringerne anvendes i denne model gør det et værdifuldt alternativ til tidligere udviklede iskæmisk hud flap-modeller.

Rotten iskæmisk sårheling model protokol bør tage ca. 20 min per dyr, hvis det sker effektivt. Før påføring af en bandage modellen skal vises som vist i figur 1G. Det vil være vigtigt at kontrollere, at bipedicled klap og sår deri er iskæmisk. Subkutan oxygenspændingen (PSCo 2) på niveau med sårene er blevet målt under validering af denne model 5 ved at placere en polarografisk elektrode i det subkutane væv mellem de to iskæmiske sår. PSCo 2 værdier var ...

Watch this Scientific Journal Video about Demonstration of the Rat Ischemic Skin Wound Model at JoVE.com

Demonstration of the Rat Ischemic Skin Wound Model

Rotter på grund af sin størrelse, tilgængelighed og snarere føjelige adfærd er blevet anvendt som et forsknings- model for mange år. Målet med denne protokol er at udnytte rotten i en iskæmisk hud sårheling model til at give værdifuld indsigt i patofysiologien af ​​kroniske sår.

Demonstration af Rat iskæmisk hudsår Model

The propensity for chronic wounds in humans increases with ageing, disease conditions such as diabetes and impaired cardiovascular function, and ...

demonstration-of-the-rat-ischemic-skin-wound-model

Research

JoVE Journal

Medicine

Accurate and Simple Measurement of the Pro-inflammatory Cytokine IL-1&beta; using a Whole Blood Stimulation Assay

Inflammatory processes resulting from the secretion of soluble mediators by immune cells, lead to various manifestations in skin, joints and other tissues as well as altered cytokine homeostasis. The innate immune system plays a crucial role in recognizing pathogens and other endogenous danger stimuli. One of the major cytokines released by innate immune cells is Interleukin (IL)-1. Therefore, we utilize a whole blood stimulation assay in order to measure the secretion of inflammatory cytokines and specifically of the pro-inflammatory cytokine IL-1&beta; 1, 2, 3.
Patients with genetic dysfunctions of the innate immune system causing autoinflammatory syndromes show an exaggerated release of mature IL-1&beta; upon stimulation with LPS alone. In order to evaluate the innate immune component of patients who present with inflammatory-associated pathologies, we use a specific immunoassay to detect cellular immune responses to pathogen-associated molecular patterns (PAMPs), such as the gram-negative bacterial endotoxin, lipopolysaccharide (LPS). These PAMPs are recognized by pathogen recognition receptors (PRRs), which are found on the cells of the innate immune system 4, 5, 6, 7. A primary signal, LPS, in conjunction with a secondary signal, ATP, is necessary for the activation of the inflammasome, a multiprotein complex that processes pro-IL-1&beta; to its mature, bioactive form 4, 5, 6, 8, 9, 10.
The whole blood assay requires minimal sample manipulation to assess cytokine production when compared to other methods that require labor intensive isolation and culturing of specific cell populations. This method differs from other whole blood stimulation assays; rather than diluting samples with a ratio of RPMI media, we perform a white blood cell count directly from diluted whole blood and therefore, stimulate a known number of white blood cells in culture 2. The results of this particular whole blood assay demonstrate a novel technique useful in elucidating patient cohorts presenting with autoinflammatory pathophysiologies.

Accurate and Simple Measurement of the Pro-inflammatory Cytokine IL-1&amp;#946; using a Whole Blood Stimulation Assay

We describe a simple immunoassay to measure the production of pro-inflammatory cytokines, such as IL-1 beta production, in patients presenting with autoinflammatory phenotypes. By activating cells in whole blood cultures with pathogen-associated molecular patterns, specifically with lipopolysaccharide, cytokine secretion can be conveniently evaluated in whole blood supernatants.

Inflammatory processes resulting from the secretion of soluble mediators by immune cells, lead to various manifestations in skin, joints and other tissues ...

A Simplified Technique for Producing an Ischemic Wound Model

One major obstacle in current diabetic wound research is a lack of an ischemic wound model that can be safely used in diabetic animals. Drugs that work well in non-ischemic wounds may not work in human diabetic wounds because vasculopathy is one major factor that hinders healing of these wounds. We published an article in 2007 describing a rabbit ear ischemic wound model created by a minimally invasive surgical technique. Since then, we have further simplified the procedure for easier operation. On one ear, three small skin incisions were made on the vascular pedicles, 1-2 cm from the ear base. The central artery was ligated and cut along with the nerve. The whole cranial bundle was cut and ligated, leaving only the caudal branch intact. A circumferential subcutaneous tunnel was made through the incisions, to cut subcutaneous tissues, muscles, nerves, and small vessels. The other ear was used as a non-ischemic control. Four wounds were made on the ventral side of each ear. This technique produces 4 ischemic wounds and 4 non-ischemic wounds in one animal for paired comparisons. After surgery, the ischemic ear was cool and cyanotic, and showed reduced movement and a lack of pulse in the ear artery. Skin temperature of the ischemic ear was 1-10 &deg;C lower than that on the normal ear and this difference was maintained for more than one month. Ear tissue high-energy phosphate contents were lower in the ischemic ear than the control ear. Wound healing times were longer in the ischemic ear than in the non-ischemic ear when the same treatment was used. The technique has now been used on more than 80 rabbits in which 23 were diabetic (diabetes time ranging from 2 weeks to 2 years). No single rabbit has developed any surgical complications such as bleeding, infection, or rupture in the skin incisions. The model has many advantages, such as little skin disruption, longer ischemic time, and higher success rate, when compared to many other models. It can be safely used in animals with reduced resistance, and can also be modified to meet different testing requirements.

We have developed a minimally invasive technique to create a rabbit ischemic ear wound model by dividing the central artery and nerve and the cranial neurovascular bundle. A subcutaneous tunnel then cuts all subcutaneous tissues. This procedure causes minimal skin disruption and can be safely used in diabetic animals.

En forenklet teknik til at producere et iskæmisk sår model

One major obstacle in current diabetic wound research is a lack of an ischemic wound model that can be safely used in diabetic animals. Drugs that work ...

Endothelin-1 Induced Middle Cerebral Artery Occlusion Model for Ischemic Stroke with Laser Doppler Flowmetry Guidance in Rat

Stroke is the number one cause of disability and third leading cause of death in the world, costing an estimated $70 billion in the United States in 20091, 2. Several models of cerebral ischemia have been developed to mimic the human condition of stroke. It has been suggested that up to 80% of all strokes result from ischemic damage in the middle cerebral artery (MCA) area3. In the early 1990s, endothelin-1 (ET-1) 4 was used to induce ischemia by applying it directly adjacent to the surface of the MCA after craniotomy. Later, this model was modified 5 by using a stereotaxic injection of ET-1 adjacent to the MCA to produce focal cerebral ischemia. The main advantages of this model include the ability to perform the procedure quickly, the ability to control artery constriction by altering the dose of ET-1 delivered, no need to manipulate the extracranial vessels supplying blood to the brain as well as gradual reperfusion rates that more closely mimics the reperfusion in humans5-7. On the other hand, the ET-1 model has disadvantages that include the need for a craniotomy, as well as higher variability in stroke volume8. This variability can be reduced with the use of laser Doppler flowmetry (LDF) to verify cerebral ischemia during ET-1 infusion. Factors that affect stroke variability include precision of infusion and the batch of the ET-1 used6. Another important consideration is that although reperfusion is a common occurrence in human stroke, the duration of occlusion for ET-1 induced MCAO may not closely mimic that of human stroke where many patients have partial reperfusion over a period of hours to days following occlusion9, 10. This protocol will describe in detail the ET-1 induced MCAO model for ischemic stroke in rats. It will also draw attention to special considerations and potential drawbacks throughout the procedure.

Several animal models of cerebral ischemia have been developed to simulate the human condition of stroke. This protocol describes the endothelin-1 (ET-1) induced middle cerebral artery occlusion (MCAO) model for ischemic stroke in rats. In addition, important considerations, advantages, and shortcomings of this model are discussed.

Endothelin-1-induceret mellem-cerebral arterieokklusion Model for iskæmisk slagtilfælde med laser-doppler-flowmetri Vejledning i Rat

Stroke is the number one cause of disability and third leading cause of death in the world, costing an estimated $70 billion in the United States in ...

Angiogenesis in the Ischemic Rat Lung

The adult lung is perfused by both the systemic bronchial artery and the entire venous return flowing through the pulmonary arteries. In most lung pathologies, it is the smaller systemic vasculature that responds to a need for enhanced lung perfusion and shows robust neovascularization. Pulmonary vascular ischemia induced by pulmonary artery obstruction has been shown to result in rapid systemic arterial angiogenesis in man as well as in several animal models. Although the histologic assessment of the time course of bronchial artery proliferation in rats was carefully described by Weibel 1, mechanisms responsible for this organized growth of new vessels are not clear. We provide surgical details of inducing left pulmonary artery ischemia in the rat that leads to bronchial neovascularization. Quantification of the extent of angiogenesis presents an additional challenge due to the presence of the two vascular beds within the lung. Methods to determine functional angiogenesis based on labeled microsphere injections are provided.

The lung is perfused by both the systemic bronchial artery and pulmonary arteries. In most lung pathologies, it is the smaller systemic vasculature that shows robust neovascularization. Cessation of pulmonary blood flow promotes brisk bronchial angiogenesis. We provide surgical details of inducing left pulmonary artery ischemia that promotes bronchial neovascularization.

Angiogenese i den iskæmiske rottelunge

The  adult lung is perfused by both the systemic bronchial artery and the entire  venous return flowing through the pulmonary arteries. In most lung ...

Murine Model of Wound Healing

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. Impaired wound healing, which occurs in diabetic patients for example, can lead to severe unfavorable outcomes such as amputation. There is, therefore, an increasing impetus to develop novel agents that promote wound repair. The testing of these has been limited to large animal models such as swine, which are often impractical. Mice represent the ideal preclinical model, as they are economical and amenable to genetic manipulation, which allows for mechanistic investigation. However, wound healing in a mouse is fundamentally different to that of humans as it primarily occurs via contraction. Our murine model overcomes this by incorporating a splint around the wound. By splinting the wound, the repair process is then dependent on epithelialization, cellular proliferation and angiogenesis, which closely mirror the biological processes of human wound healing. Whilst requiring consistency and care, this murine model does not involve complicated surgical techniques and allows for the robust testing of promising agents that may, for example, promote angiogenesis or inhibit inflammation. Furthermore, each mouse acts as its own control as two wounds are prepared, enabling the application of both the test compound and the vehicle control on the same animal. In conclusion, we demonstrate a practical, easy-to-learn, and robust model of wound healing, which is comparable to that of humans.

A murine model of cutaneous wound healing that can be used to assess therapeutic compounds in physiological and pathophysiological settings.

Musemodel af Sårheling

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. ...

Ischemic Tissue Injury in the Dorsal Skinfold Chamber of the Mouse: A Skin Flap Model to Investigate Acute Persistent Ischemia

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are still occurring, particularly in reconstructive flap surgery. Multiple experimental flap models have been developed to analyze underlying causes and mechanisms and to investigate treatment strategies to prevent ischemic complications. The limiting factor of most models is the lacking possibility to directly and repetitively visualize microvascular architecture and hemodynamics. The goal of the protocol was to present a well-established mouse model affiliating these before mentioned lacking elements. Harder et al. have developed a model of a musculocutaneous flap with a random perfusion pattern that undergoes acute persistent ischemia and results in ~50% necrosis after 10 days if kept untreated. With the aid of intravital epi-fluorescence microscopy, this chamber model allows repetitive visualization of morphology and hemodynamics in different regions of interest over time. Associated processes such as apoptosis, inflammation, microvascular leakage and angiogenesis can be investigated and correlated to immunohistochemical and molecular protein assays. To date, the model has proven feasibility and reproducibility in several published experimental studies investigating the effect of pre-, peri- and postconditioning of ischemically challenged tissue.

The window of the murine dorsal skinfold chamber presented visualizes a zone of acute persistent ischemia of a musculocutaneous flap. Intravital epi-fluorescence microscopy permits for direct and repetitive assessment of the microvasculature and quantification of hemodynamics. Morphologic and hemodynamic results can further be correlated with histological and molecular analyses.

Iskæmisk væv skade i Dorsal hudfolden Afdeling Mus: En hudlap modellen til Akut Persistent Iskæmi

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are ...

A Mouse Fetal Skin Model of Scarless Wound Repair

Early in utero, but not in postnatal life, cutaneous wounds undergo regeneration and heal without formation of a scar. Scarless fetal wound healing occurs across species but is age dependent. The transition from a scarless to scarring phenotype occurs in the third trimester of pregnancy in humans and around embryonic day 18 (E18) in mice. However, this varies with the size of the wound with larger defects generating a scar at an earlier gestational age. The emergence of lineage tracing and other genetic tools in the mouse has opened promising new avenues for investigation of fetal scarless wound healing. However, given the inherently high rates of morbidity and premature uterine contraction associated with fetal surgery, investigations of fetal scarless wound healing in vivo require a precise and reproducible surgical model. Here we detail a reliable model of fetal scarless wound healing in the dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.

During mammalian development, early gestational skin wounds heal without a scar. Here we detail a reliable and reproducible model of fetal scarless wound healing in the cutaneous dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.

En mus Føtal Skin Model af scarless sårheling

Early in utero, but not in postnatal life, cutaneous wounds undergo regeneration and heal without formation of a scar. Scarless fetal wound healing occurs ...

Rat Model of Photochemically-Induced Posterior Ischemic Optic Neuropathy

Posterior Ischemic optic neuropathy (PION) is a sight-devastating disease in clinical practice. However, its pathogenesis and natural history have&#160;remained poorly understood. Recently, we developed a reliable, reproducible animal model of PION and tested the treatment effect of some neurotrophic factors in this model1. The purpose of this video is to demonstrate our photochemically induced model of posterior ischemic optic neuropathy, and to evaluate its effects with retrograde labeling of retinal ganglion cells. Following surgical exposure of the posterior optic nerve, a photosensitizing dye, erythrosin B, is intravenously injected and a laser beam is focused onto the optic nerve surface. Photochemical interaction of erythrosin B and the laser during irradiation damages the vascular endothelium, prompting microvascular occlusion mediated by platelet thrombosis and edematous compression. The resulting ischemic injury yields a gradual but pronounced retinal ganglion cell dieback, owing to a loss of axonal input - a remote, injury-induced and clinically relevant outcome. Thus, this model provides a novel platform to study the pathophysiologic course of PION,&#160;and can be further optimized for testing therapeutic approaches for optic neuropathies as well as other CNS ischemic diseases.

The goal of this protocol is to photochemically induce ischemic injury to the posterior optic nerve in rat. This model is critical to studies of the pathophysiology of posterior ischemic optic neuropathy, and therapeutic approaches for this and other optic neuropathies, as well as of other CNS ischemic diseases.

Rotte model af fotokemisk-induceret posterior iskæmisk opticusneuropati

Posterior Ischemic optic neuropathy (PION) is a sight-devastating disease in clinical practice. However, its pathogenesis and natural history ...

A Piglet Model of Neonatal Hypoxic-Ischemic Encephalopathy

Birth asphyxia, which causes hypoxic-ischemic encephalopathy (HIE), accounts for 0.66 million deaths worldwide each year, about a quarter of the world&#8217;s 2.9 million neonatal deaths. Animal models of HIE have contributed to the understanding of the pathophysiology in HIE, and have highlighted the dynamic process that occur in brain injury due to perinatal asphyxia. Thus, animal studies have suggested a time-window for post-insult treatment strategies. Hypothermia has been tested as a treatment for HIE in pdiglet models and subsequently proven effective in clinical trials. Variations of the model have been applied in the study of adjunctive neuroprotective methods and piglet studies of xenon and melatonin have led to clinical phase I and II trials1,2. The piglet HIE model is further used for neonatal resuscitation- and hemodynamic studies as well as in investigations of cerebral hypoxia on a cellular level. However, it is a technically challenging model and variations in the protocol may result in either too mild or too severe brain injury. In this article, we demonstrate the technical procedures necessary for establishing a stable piglet model of neonatal HIE. First, the newborn piglet (&#60; 24 hr old, median weight 1500 g) is anesthetized, intubated, and monitored in a setup comparable to that found in a neonatal intensive care unit. Global hypoxia-ischemia is induced by lowering the inspiratory oxygen fraction to achieve global hypoxia, ischemia through hypotension and a flat trace amplitude integrated EEG (aEEG) indicative of cerebral hypoxia. Survival is promoted by adjusting oxygenation according to the aEEG response and blood pressure. Brain injury is quantified by histopathology and magnetic resonance imaging after 72 hr.

Hypoxic-ischemic encephalopathy following perinatal asphyxia can be studied using animal models. We demonstrate the procedures necessary for establishing a piglet model of neonatal hypoxic-ischemic encephalopathy.

En Grisling Model for Neonatal Hypoksisk-iskæmisk encephalopati

Birth asphyxia, which causes hypoxic-ischemic encephalopathy (HIE), accounts for 0.66 million deaths worldwide each year, about a quarter of the ...

The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy (rNAION)

Nonarteritic anterior ischemic optic neuropathy (NAION) is a focal ischemic lesion of the optic nerve that affects 1/700 individuals throughout their lifetime. NAION results in optic nerve edema, selective loss of the retinal ganglion cell neurons (RGCs) and atrophy of the optic nerve. A rodent model of NAION that expresses most NAION features and sequelae has been developed, which is applicable to both rats and mice. This model utilizes a focal laser application of 532 nm wavelength to illuminate a photoactive dye, Rose Bengal (RB), to cause capillary damage and leakage at the targeted anterior optic nerve (the laminar region). After rNAION induction, there is an early optic nerve ischemia, optic nerve edema, and intraneural inflammation, followed by selective RGC and axonal loss. Since the optic nerve is a CNS white matter tract, the rNAION model is applicable to mechanistic studies of selective white matter ischemia, as well as neuroprotective analyses and short and long-term mechanisms of glial and neuronal response to ischemia.

The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy rNAION

The following report describes how to replicate the rodent model of nonarteritic anterior ischemic optic neuropathy (rNAION), using the appropriate dye, contact lens and laser parameters. We also reveal the appropriate steps for evaluating the rNAION lesion in vivo.

Den gnaver Model of Nonarteritic anterior iskæmisk opticusneuropati (rNAION)

Nonarteritic anterior ischemic optic neuropathy (NAION) is a focal ischemic lesion of the optic nerve that affects 1/700 individuals throughout their ...