1. Mouse Anesthesia Procedures
<ol>
	<li>Animals are removed from their cage and placed in an anesthetic pre-operative induction chamber for gas induction at 5% isoflurane and 100% oxygen, at a flow rate of 0.5 liters per minute (vaporizer controlled).</li>
	<li>Mice are sedated in the anesthetic induction chamber, removed from chamber and the ventral abdomen is shaved with electric clippers, or maintained within the chamber if a hair depilatory is used (1min).</li>
	<li>While still under sedation, they are weighed, the eyes are lubricated with sterile opthalmic ointment and then placed in a dorsal recumbancy on a warm water circulating heating device under general anesthesia, with a nose cone, using isoflurane and oxygen. At this point the oxygen rate is reduced to 0.2 liters per minute.</li>
	<li>The abdomen is sprayed with chlorhexidine solution (chlorhexidine diacetate is rapidly bacterialcidal and persistent) and wiped with sterile gauze three times or until the surgical site is clean.</li>
</ol>
2. Mouse Micro-surgical and Recovery Procedures
<ol>
	<li>A ventral midline incision (2cm) is made with iris scissors through the skin and abdominal wall exposing the abdomen. A sterile saline soaked 2x2in gauze is used to reflect the intestines to the animal&#x2019;s left side. A mouse restrainer is put in place allowing visualization of the inferior vena cava (IVC).</li>
	<li>At this point, a maintenance level of 2% isoflurance and 100% oxygen rate of 0.2 liters/min is used for the remainder of the surgical procedure.</li>
	<li>Blunt dissection is facilitated using a sterile applicator swab and extra delicate iris half curved tissue forceps. Care must be taken
	in handling mouse tissues for they are extremely fragile. Upon entering the abdominal cavity, use a sterile saline soaked 4x4in gauze
	to reflect and exteriorize the intestines onto a sterile drape, thus allowing visualization of the IVC.</li>
	<li>All IVC back branches, from the renal veins to the iliac bifurcation, are cauterized while side branches are ligated with 7-0 non-reactive prolene sutures.</li>
	<li>The IVC is separated from the aorta, just inferior to the renal veins. 7-0 prolene is used to ligate the IVC.</li>
	<li>The laparotomy site is closed in a two-layer fashion. Our laboratory uses 5-0 vicryl, a synthetic suture, in a continuous pattern to close the abdominal wall. Adhesive skin glue is used to close the skin. There are no external sutures for removal.</li>
	<li>Mice are then recovered in an individual mouse cage, observed post-operatively (45 minutes to 2 hours) under a heating lamp (minimum
	distance- 24 inches away from cage), then returned to their original housing units. Pain medication and anti-inflammatory agents can be
	used if it does not interfere with study objective. Scientific justification to withhold pain medications, veterinary, and ICUCA
	approval are needed. Our laboratory has found that Buprenorphine, 0.05-0.1 mg/kg SQ is an excellent pre- and post-operative analgesic
	for mice. In addition, Lidocaine at 4mg/kg (0.4 ml/kg of a 1% solution) can be infused in the incision site when systemic analgesics
	may confound experimental results.</li>
	<li>Sham animals from each experimental group undergo the above dissection used for the surgical approach, except the IVC or any draining branches are not ligated or cauterized.</li>
	<li>Euthanasia is performed in accordance with the recommendations set forth by the American Veterinary Medical Association Guidelines on Euthanasia for rodents.</li>
</ol>

<ol>
	<li>Naess, I. A., Christiansen, S. C., Romundstad, P., Cannegieter, S. C., Rosendaal, F. R., Hammerstrom, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Incidence+and+mortality+of+venous+thrombosis:+a+population-based+study.">Incidence and mortality of venous thrombosis: a population-based study.</a> J Thromb Haemost. 5, 692-699 (2007).</li><li>White, R. H., Keenan, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+race+and+ethnicity+on+the+incidence+of+venous+thromboembolism.">Effects of race and ethnicity on the incidence of venous thromboembolism.</a> Thromb Res. 123, S11-S17 (2009).</li><li>Heit, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+epidemiology+of+venous+thromboembolism+in+the+community.">The epidemiology of venous thromboembolism in the community.</a> Arterioscler Thromb Vasc Biol. 28, 370-372 (2008).</li><li>Henke, P. K., Varga, A., De, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deep+vein+thrombosis+resolution+is+modulated+by+monocyte+CXCR2-mediated+activity+in+a+mouse+model.">Deep vein thrombosis resolution is modulated by monocyte CXCR2-mediated activity in a mouse model.</a> Arterioscler Thromb Vasc Biol. 24, 1130-1137 (2004).</li><li>McDonald, A. P., Meier, T. R., Hawley, A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aging+is+associated+with+impaired+thrombus+resolution+in+a+mouse+model+of+stasis+induced+thrombosis.">Aging is associated with impaired thrombus resolution in a mouse model of stasis induced thrombosis.</a> Thromb Res. 125, 72-78 (2010).</li><li>Myers, D., Farris, D., Hawley, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selectins+influence+thrombosis+in+a+mouse+model+of+experimental+deep+venous+thrombosis.">Selectins influence thrombosis in a mouse model of experimental deep venous thrombosis.</a> J Surg Res. 108, 212-221 (2002).</li><li>Myers, D. D., Hawley, A. E., Farris, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=P-selectin+and+leukocyte+microparticles+are+associated+with+venous+thrombogenesis.">P-selectin and leukocyte microparticles are associated with venous thrombogenesis.</a> J Vasc Surg. 38, 1075-1089 (2003).</li><li>Myers, D. D. J. r., Rectenwald, J. E., Bedard, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Decreased+venous+thrombosis+with+an+oral+inhibitor+of+P+selectin.">Decreased venous thrombosis with an oral inhibitor of P selectin.</a> J Vasc Surg. 42, 329-336 (2005).</li></ol>

No conflicts of interest declared.

The Mouse Complete Stasis Model of Inferior Vena Cava Thrombosis can be performed on multiple strains of mice of varying ages. The model is most suited to mice of at least 20 grams in weight. This animal model of venous thrombosis allows investigators to study inflammatory interactions between the vein wall and the occlusive venous thrombus. From our experience, we have found that 10 or more animals per group are needed to obtain statistical significance between the groups for thrombus weights, vein wall inflammatory cel...

<table border="1">
	<tbody>
 	<tr>
 	<td>Supplies and Equipment</td>
 </tr>
 <tr>
 	<td>Isoflurane gas</td>
 </tr>
 <tr>
 	<td>Prolene 7-0 suture</td>
 </tr>
 <tr>
 	<td>Vicryl 5-0 suture</td>
 </tr>
 <tr>
 	 <td>Skin glue</td>
 </tr>
 <tr>
 <td>Eye lube </td>
 </tr>
 <tr>
 <td>Nolvasan Solution or bacteriostatic solution</td>
 </tr>
 <tr>
 <td>Stereomicroscope scope</td>
 </tr>
 <tr>
 		<td>MediCapture</td>
 </tr>
 <tr>
 		<td>Cotton Applicators</td>
 </tr>
 <tr>
 		<td>2x2 Gauze</td>
 </tr>
 <tr>
 		<td>Heating pad</td>
 </tr>
		<tr>
 		<td>Anesthetic machine</td>
 </tr>
		<tr>
 		<td>Glass bead instrument sterilizer</td>
 </tr>
 <tr>
 		<td>Micro surgical instruments</td>
 </tr>
 <tr>
 		<td>Abdominal Restrainers</td>
 </tr>
 </tbody>
</table>

mouse complete stasis model of inferior vena cava thrombosis

Venous thromboembolism (VTE) includes both deep vein thrombosis (DVT) and pulmonary embolism (PE). In the United States (U.S.), the high morbidity and mortality rates make VTE a serious health concern 1-2. After heart disease and stroke, VTE is the third most common vascular disease 3. In the U.S. alone, there is an estimated 900,000 people affected each year, with 300,000 deaths occurring annually 3. A reliable in vivo animal model to study the mechanisms of this disease is necessary.
The advantages of using the mouse complete stasis model of inferior vena cava thrombosis are several. The mouse model allows for the administration of very small volumes of limited availability test agents, reducing costs dramatically. Most promising is the potential for mice with gene knockouts that allow specific inflammatory and coagulation factor functions to be delineated. Current molecular assays allow for the quantitation of vein wall, thrombus, whole blood, and plasma for assays. However, a major concern involving this model is the operative size constraints and the friability of the vessels. Also, due to the small IVC sample weight (mean 0.005 grams) it is necessary to increase animal numbers for accurate statistical analysis for tissue, thrombus, and blood assays such as real-time polymerase chain reaction (RT-PCR), western blot, enzyme-linked immunosorbent (ELISA), zymography, vein wall and thrombus cellular analysis, and whole blood and plasma assays 4-8.
The major disadvantage with the stasis model is that the lack of blood flow inhibits the maximal effect of administered systemic therapeutic agents on the thrombus and vein wall.

Watch this Scientific Journal Video about Mouse Complete Stasis Model of Inferior Vena Cava Thrombosis at JoVE.com

Mouse Complete Stasis Model of Inferior Vena Cava Thrombosis

The mouse complete stasis model of inferior vena cava thrombosis yields quantifiable amounts of vein wall tissue and thrombus. It has proven useful for evaluating interactions between the vein wall and the occlusive thrombus and in assessing the progression from acute to chronic inflammation.

Venous thromboembolism (VTE) includes both deep vein thrombosis (DVT) and pulmonary embolism (PE).  In the United States (U.S.), the high morbidity and ...

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18.1K Views.  University of Michigan. The mouse complete stasis model of inferior vena cava thrombosis yields quantifiable amounts of vein wall tissue and thrombus. It has proven useful for evaluating interactions between the vein wall and the occlusive thrombus and in assessing the progression from acute to chronic inflammation.

Video: Mouse Complete Stasis Model of Inferior Vena Cava Thrombosis

Electrolytic Inferior Vena Cava Model (EIM) of Venous Thrombosis

Animal models serve a vital role in deep venous thrombosis (DVT) research in order to study thrombus formation, thrombus resolution and to test potential therapeutic compounds (1). New compounds to be utilized in the treatment and prevention of DVT are currently being developed. The delivery of potential therapeutic antagonist compounds to an affected thrombosed vein has been problematic. In the context of therapeutic applications, a model that uses partial stasis and consistently generates thrombi within a major vein has been recently established. The Electrolytic Inferior vena cava Model (EIM) is mouse model of DVT that permits thrombus formation in the presence of continuous blood flow. This model allows therapeutic agents to be in contact with the thrombus in a dynamic fashion, and is more sensitive than other models of DVT (1). In addition, this thrombosis model closely simulates clinical situations of thrombus formation and is ideal to study venous endothelial cell activation, leukocyte migration, venous thrombogenesis, and to test therapeutic applications (1). The EIM model is technically simple, easily reproducible, creates consistent thrombi sizes and allows for a large sample (i.e. thrombus and vein wall) which is required for analytical purposes.

Electrolytic Inferior Vena Cava Model EIM of Venous Thrombosis

The electrolytic induction of endothelial activation to the internal surface of the Inferior Vena Cava results in venous type thrombus formation due to endothelial activation and partial blood stasis, two components of Virchow's triad.

Animal models serve a vital role in deep venous thrombosis (DVT) research in order to study thrombus formation, thrombus resolution and to test potential ...

Quantitative Analysis and Characterization of Atherosclerotic Lesions in the Murine Aortic Sinus

Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have been developed to facilitate the study of the molecular and cellular pathophysiology of this disease. In this manuscript we describe specific techniques for the quantification and characterization of atherosclerotic lesions in the murine aortic sinus and ascending aorta. The advantage of this procedure is that it provides an accurate measurement of the cross-sectional area and total volume of the lesion, which can be used to compare atherosclerotic progression across different treatment groups. This is possible through the use of the valve leaflets as an anatomical landmark, together with careful adjustment of the sectioning angle. We also describe basic staining methods that can be used to begin to characterize atherosclerotic progression. These can be further modified to investigate antigens of specific interest to the researcher. The described techniques are generally applicable to a wide variety of existing and newly created dietary and genetically-induced models of atherogenesis.

We describe procedures to quantify and characterize atherosclerotic lesions in mouse models using precision sectioning of the aortic sinus and ascending aorta combined with histochemical and immunohistochemical analysis.

Atherosclerosis is a disease of the large arteries and a major underlying cause of myocardial infarction and stroke. Several different mouse models have ...

Implantation of Inferior Vena Cava Interposition Graft in Mouse Model

Biodegradable scaffolds seeded with bone marrow mononuclear cells (BMCs) are often used for reconstructive surgery to treat congenital cardiac anomalies. The long-term clinical results showed excellent patency rates, however, with significant incidence of stenosis. To investigate the cellular and molecular mechanisms of vascular neotissue formation and prevent stenosis development in tissue engineered vascular grafts (TEVGs), we developed a mouse model of the graft with approximately 1 mm internal diameter. First, the TEVGs were assembled from biodegradable tubular scaffolds fabricated from a polyglycolic acid nonwoven felt mesh coated with &#949;-caprolactone and L-lactide copolymer. The scaffolds were then placed in a lyophilizer, vacuumed for 24 hr, and stored in a desiccator until cell seeding. Second, bone marrow was collected from donor mice and mononuclear cells were isolated by density gradient centrifugation. Third, approximately one million cells were seeded on a scaffold and incubated O/N. Finally, the seeded scaffolds were then implanted as infrarenal vena cava interposition grafts in C57BL/6 mice. The implanted grafts demonstrated excellent patency (&#62;90%) without evidence of thromboembolic complications or aneurysmal formation. This murine model will aid us in understanding and quantifying the cellular and molecular mechanisms of neotissue formation in the TEVG.

To improve our knowledge of cellular and molecular neotissue formation, a murine model of the TEVG was recently developed. The grafts were implanted as infrarenal vena cava interposition grafts in C57BL/6 mice. This model achieves similar results to those achieved in our clinical investigation, but over a far shortened time-course.

Biodegradable scaffolds seeded with bone marrow mononuclear cells (BMCs) are often used for reconstructive surgery to treat congenital cardiac anomalies. ...

Orthotopic Injection of Breast Cancer Cells into the Mammary Fat Pad of Mice to Study Tumor Growth.

Breast cancer growth can be studied in mice using a plethora of models. Genetic manipulation of breast cancer cells may provide insights into the functions of proteins involved in oncogenic progression or help to discover new tumor suppressors. In addition, injecting cancer cells into mice with different genotypes might provide a better understanding of the importance of the stromal compartment. Many models may be useful to investigate certain aspects of disease progression but do not recapitulate the entire cancerous process. In contrast, breast cancer cells engraftment to the mammary fat pad of mice better recapitulates the location of the disease and presence of the proper stromal compartment and therefore better mimics human cancerous disease. In this article, we describe how to implant breast cancer cells into mice orthotopically and explain how to collect tissues to analyse the tumor milieu and metastasis to distant organs. Using this model, many aspects (growth, angiogenesis, and metastasis) of cancer can be investigated simply by providing a proper environment for tumor cells to grow.

Cancer is a complex disease that is influenced by the tissue surrounding the tumor as well as local pro- and anti-inflammatory mediators. Therefore, orthotropic injection models, rather than subcutaneous models may be useful to study cancer progression in a manner that better mimics human pathology.

Breast cancer growth can be studied in mice using a plethora of models. Genetic manipulation of breast cancer cells may provide insights into the ...

Ferric Chloride-induced Thrombosis Mouse Model on Carotid Artery and Mesentery Vessel

Severe thrombosis and its ischemic consequences such as myocardial infarction, pulmonary embolism and stroke are major worldwide health issues. The ferric chloride injury is now a well-established technique to rapidly and accurately induce the formation of thrombi in exposed veins or artery of small and large diameter. This model has played a key role in the study of the pathophysiology of thrombosis, in the discovery and validation of novel antithrombotic drugs and in the understanding of the mechanism of action of these new agents. Here, the implementation of this technique on a mesenteric vessel and carotid artery in mice is presented. The method describes how to label circulating leukocytes and platelets with a fluorescent dye and to observe, by intravital microscopy on the exposed mesentery, their accumulation at the injured vessel wall which leads to the formation of a thrombus. On the carotid artery, the occlusion caused by the clot formation is measured by monitoring the blood flow with a Doppler probe.

The FeCl3 induced thrombosis model in mice is described herein. A method to monitor thrombus growth by intravital microscopy observation on a mesenteric vessel and by blood flow measurement in the carotid artery is presented.

Severe thrombosis and its ischemic consequences such as myocardial infarction, pulmonary embolism and stroke are major worldwide health issues. The ferric ...

Ferric Chloride-induced Murine Thrombosis Models

Arterial thrombosis (blood clot) is a common complication of many systemic diseases associated with chronic inflammation, including atherosclerosis, diabetes, obesity, cancer and chronic autoimmune rheumatologic disorders. Thrombi are the cause of most heart attacks, strokes and extremity loss, making thrombosis an extremely important public health problem. Since these thrombi stem from inappropriate platelet activation and subsequent coagulation, targeting these systems therapeutically has important clinical significance for developing safer treatments. Due to the complexities of the hemostatic system, in vitro experiments cannot replicate the blood-to-vessel wall interactions; therefore, in vivo studies are critical to understand pathological mechanisms of thrombus formation. To this end, various thrombosis models have been developed in mice. Among them, ferric chloride (FeCl3) induced vascular injury is a widely used model of occlusive thrombosis that reports platelet activation and aggregation in the context of an aseptic closed vascular system. This model is based on redox-induced endothelial cell injury, which is simple and sensitive to both anticoagulant and anti-platelets drugs. The time required for the development of a thrombus that occludes blood flow gives a quantitative measure of vascular injury, platelet activation and aggregation that is relevant to thrombotic diseases. We have significantly refined this FeCl3-induced vascular thrombosis model, which makes the data highly reproducible with minimal variation. Here we describe the model and present representative data from several experimental set-ups that demonstrate the utility of this model in thrombosis research.

We report a refined procedure of the ferric chloride (FeCl3)-induced thrombosis models on carotid and mesenteric artery as well as vein, characterized efficiently using intravital microscopy to monitor time to occlusive thrombi formation.

Arterial thrombosis (blood clot) is a common complication of many systemic diseases associated with chronic inflammation, including atherosclerosis, ...

Patch Angioplasty in the Rat Aorta or Inferior Vena Cava

Pericardial patches are commonly used in vascular surgery to close vessels. To facilitate studies of the neointimal hyperplasia that forms on the patch, we developed a rat model of patch angioplasty that can be used in either a vein or an artery, creating a patch venoplasty or a patch arterioplasty, respectively. Technical aspects of this model are discussed. The infra-renal IVC or aorta are dissected and then clamped proximally and distally. A 3 mm venotomy or arteriotomy is performed in the infrarenal inferior vena cava or aorta of 6 to 8 week-old Wistar rats. A bovine pericardial patch (3 mm x 1.5 mm x 0.6 mm) is then used to close the site using a 10-0 nylon suture. Compared to arterial patches, venous patches show increased neointimal thickness on postoperative day 7. This novel model of pericardial patch angioplasty can be used to examine neointimal hyperplasia on vascular biomaterials, as well as to compare the differences between the arterial and venous environments.

We have established a model of pericardial patch angioplasty that can be used in either small-diameter veins or arteries. This model can be used to compare venous and arterial neointimal hyperplasia formation.

Pericardial patches are commonly used in vascular surgery to close vessels. To facilitate studies of the neointimal hyperplasia that forms on the patch, ...

A Rat Model of Orthotopic Liver Transplantation Using a Novel Magnetic Anastomosis Technique for Suprahepatic Vena Cava Reconstruction

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research. It is a very sophisticated animal model and requires a steep learning curve. The introduction of the cuff technique for anastomosis of the portal vein (PV) and infrahepatic vena cava (IHVC) has significantly simplified the transplant procedure in rats. However, due to the short anterior wall of the recipients' suprahepatic vena cava (SHVC), the cuff technique is very difficult to use for the reconstruction of the SHVC. Most researchers in this field still use the hand-suture technique for SHVC reconstruction, which makes it the bottleneck step in rat orthotopic liver transplantation. The magnetic anastomosis technique (i.e., magnamosis) is a method of connecting two vessels using the attractive force between two magnets. Our recent study has shown that the magnetic anastomosis technique is superior to the hand-suture technique for SHVC reconstruction in rats. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using the novel magnetic anastomosis technique. In this model, the reconstruction of the PV and IHVC was performed by the standard cuff technique, while the reconstruction of the bile duct (BD) was performed by a stent technique. The hepatic re-arterialization was not performed. The magnetic anastomosis technique made SHVC reconstruction much easier and significantly shortened the anphepatic phase. After a reasonable learning curve, even researchers without advanced microsurgical skills can produce reliable and reproducible results using this rat model of OLT.

The reconstruction of the suprahepatic vena cava (SHVC) remains a difficult step in rat orthotopic liver transplantation. In this article, we show a step-by-step protocol for SHVC reconstruction in rats using a novel magnetic anastomosis technique.

The rat model of orthotopic liver transplantation (OLT) is essential for transplant research. It is a very sophisticated animal model and requires a steep ...

Ferric Chloride-induced Canine Carotid Artery Thrombosis: A Large Animal Model of Vascular Injury

Occlusive arterial thrombosis leading to cerebral ischemic stroke and myocardial infarction contributes to ~13 million deaths every year globally. Here, we have translated a vascular injury model from a small animal into a large animal (canine), with slight modifications that can be used for pre-clinical screening of prophylactic and thrombolytic agents. In addition to the surgical methods, the modified protocol describes the step-by-step methods to assess carotid artery canalization by angiography, detailed instructions to process both the brain and carotid artery for histological analysis to verify carotid canalization and cerebral hemorrhage, and specific parameters to complete an assessment of downstream thromboembolic events by utilizing magnetic resonance imaging (MRI). In addition, specific procedural changes from the previously well-established small animal model necessary to translate into a large animal (canine) vascular injury are discussed.

Here, we present the modifications necessary to a well characterized and commonly used small animal ferric chloride-induced (FeCl3) carotid artery injury model for use in a large animal vascular injury model. The resulting model can be utilized for pre-clinical trial assessment of both prophylactic and thrombolytic pharmacological and mechanical interventions.

Occlusive arterial thrombosis leading to cerebral ischemic stroke and myocardial infarction contributes to ~13 million deaths every year globally. Here, ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...