This study was partially supported by NIH grant RO1NS053407 to J.H. Zhang. We would like to thank Mr. Damon Klebe for his valuable contributions.

All procedures were conducted in compliance with the NIH Guide for the Care and Use of Laboratory Animals and approved by the Animal Care and Use Committee at Loma Linda University.
1. Presurgical Preparations
Aseptic techniques are recommended for all surgical procedures. Disinfect the stereotactic apparatus and prepare sterile surgical tools prior to surgery. Wear personal protective equipment (PPE) during all animal handling. Use a heating pad during surgery to maintain the animal's physiologic body temperature.
<ol>
	<li>Weigh the 8-12 week old mouse using a triple beam animal scale.</li>
	<li>Co-inject ketamine (100 mg/kg) and xylazine (10 mg/kg) intraperitoneally then allow 7-10 min for the anesthesia to take effect (monitor for an adequate sedation).</li>
	<li>Place the mouse onto a thermal blanket and shave the scalp.</li>
	<li>Apply ophthalmic ointment to both eyes.</li>
	<li>Secure the airway, by gently moving the tongue laterally, and carefully secure the mouse's head onto the stereotactic apparatus. Note: The head must be secured horizontally to the basis of the stereotactic frame.</li>
	<li>Disinfect the surgical area with Betadine, and rinse with 70% ethanol. Repeat alternating applications of Betadine and 70% ethanol for a total of three times. Cotton-tipped applicators can be used for this purpose.</li>
</ol>
2. Blood Injection Model
<ol>
	<li>Make a 1 cm long midline incision of the scalp with a #10 scalpel blade.</li>
	<li>Use cotton-tipped applicators to clear away the soft tissue covering the skull, in order to expose the perpendicular intersection point of the coronal and sagittal suture (bregma).</li>
	<li>Mount the Hamilton syringe (250 &mu;l) onto the injection pump, and stereotaxically direct the needle (26 Gauge) over bregma.</li>
	<li>Next, adjust the stereotactic manipulator arms to position the needle 0.2 mm anterior and 2 mm laterally to the right. At these coordinates make a small cranial burr hole, using a variable speed drill with a 1 mm drill bit.</li>
	<li>Suspend the animal's tail and disinfect its lower surface with 70% ethanol.</li>
	<li>Puncture the central tail artery with a sterile needle (e.g. 26 Gauge) and collect the arterial blood into an unheparinized capillary tube.</li>
	<li>Transfer the blood quickly from the capillary tube into the glass barrel of the Hamilton syringe, then insert the plunger.</li>
	<li>Reattach the now 30 &mu;l or more of arterial blood containing Hamilton syringe onto the injection pump and insert the needle (with its beveled edge facing the sagittal suture) through the burr hole just until its bevel is no longer visible.</li>
	<li>From this point advance the needle 3 mm ventrally and inject 5 &mu;l of autologous blood at a rate of 2 &mu;l/min.</li>
	<li>After completion of the first injection advance the needle 0.7 mm further in depth.</li>
	<li>Wait for 5 min then inject 25 &mu;l of blood into the right striatum.</li>
	<li>Upon completion of the second injection, leave the needle in position for additional 10 min, before withdrawing it at a rate of 1 mm/min.</li>
	<li>Seal the burr hole with bone wax and suture the skin.</li>
	<li>For postoperative analgesia inject 0.05 mg/kg of buprenorphine subcutaneously in pre-warmed fluids (normal saline).</li>
</ol>
3. Collagenase Injection Model
<ol>
	<li>Following the presurgical preparations, repeat steps 1-4 as described for the blood injection model.</li>
	<li>Fill the Hamilton syringe (10 &mu;l) with 0.075U of bacterial (clostridial) collagenase VII-S dissolved in 0.5 &mu;l of saline. Avoid the formation of air bubbles.</li>
	<li>Reattach the Hamilton syringe onto the injection pump and insert the needle (26 Gauge), through the burr hole just until its bevel is no longer visible.</li>
	<li>Advance the needle 3.7 mm ventrally and inject the 0.075U of collagenase into the right striatum at a rate of 2 &mu;l/min.</li>
	<li>Upon completion of the injection, leave the needle in position for additional 10 min, before withdrawing it at a rate of 1 mm/min.</li>
	<li>Seal the burr hole with bone wax and suture the skin.</li>
	<li>Inject 0.05 mg/kg of buprenorphine subcutaneously in pre-warmed post-operative fluids.</li>
</ol>
4. Sham Operation
<ol>
	<li>Following the presurgical preparations, repeat steps 1-4 as described for the blood injection model.</li>
	<li>Insert the needle (26 Gauge) 3.7 mm ventrally through the burr hole. The needle should remain in position for 10 min before being withdrawn at a rate of 1 mm/min.</li>
	<li>Seal the burr hole with bone wax and suture the skin.</li>
	<li>Inject 0.05 mg/kg of buprenorphine subcutaneously in pre-warmed post-operative fluids.</li>
</ol>
5. Representative Results
Experimental intrastriatal hemorrhage evokes morphological as well as behavioral changes in rodents. These changes can be evaluated to ensure an adequate execution of the procedure, or to investigate the effects of potential treatments. Generating the bleed in a targeted brain area (e.g. basal ganglia) is most essential for a reproducible approach, and can be verified on gross or histologically stained brain sections (Figure 1-2). Injury to the basal ganglia results in sensorimotor deficits, which can be quantified via various behavioral assessments. Results of the corner turn test showed that, after experimental right-sided ICH, mice turned significantly more often ipsilaterally and away from the impaired contralateral (left) side, than sham operated animals at 24 and 72 hr after surgery (Figure 3 A). Furthermore, the ability to adequately place the impaired (left) forelimb on a surface, following vibrissae stimulation, was evaluated via the forelimb placing test. At 24 and 72 hr after surgery, mice subjected to right-sided ICH showed significantly fewer placements than sham operated animals. Measurement of brain edema is frequently employed to quantify the extent of brain injury after experimental ICH. Intracerebral injections of autologous blood (30 &mu;l) or bacterial collagenase (0.075 U) led to a significant increase of brain water content in the ipsilateral cortex and basal ganglia at 24 (Figure 4 A) and 72 hr (Figure 4 B) after surgery (compared to sham). The outcome of the behavior tests (Figure 3) and the extent of brain edema (Figure 4) showed no difference between the blood and collagenase injection models at given volumes.
<img alt="Figure 1" src="/files/ftp_upload/4289/4289fig1.jpg" /> 
Figure 1. Modeling ICH in mice. (A) The simplified schematic of a coronal brain section 0.2 mm anterior of bregma illustrates the proposed location of autologous blood or collagenase injection. The lateral ventricle is marked LV. CPu stands for caudate-putamen, a part of the striatum, and GP identifies the globus pallidus. Both, the striatum as well as the globus pallidus belong to a group of sub-cortical nuclei, also known as basal ganglia. (B) Representative photomicrograph of a coronal brain section 0.2mm anterior of bregma, obtained at 24 hr after intrastriatal injection of autologous whole blood.
<img alt="Figure 2" src="/files/ftp_upload/4289/4289fig2.jpg" /> 
Figure 2. Histological manifestation of the hematoma. Representative hematoxylin and eosin (H&amp;E) stained coronal cryosection (10 &mu;m) of a mouse brain, illustrating hematoma size at 24 hr after intrastriatal injection of bacterial collagenase (0.075 U). LH=left hemisphere, RH=right hemisphere.
<img alt="Figure 3" src="/files/ftp_upload/4289/4289fig3.jpg" /> 
Figure 3. Neurofunctional assessments following experimental ICH in mice. Intrastriatal injection of autologous blood (30 &mu;l) or bacterial collagenase (0.075 U) caused reproducible neurofunctional deficits. (A) Mice after experimental ICH showed significantly more right turns than sham operated animals at 24 and 72 hr after surgery. (B) Forepaw placing capacity of the left limb was impaired after ICH at 24 and 72 hr after surgery. Values were expressed as mean&plusmn;S.E.M. and analyzed with Kruskal-Wallis One Way Analysis of Variance on Ranks, followed by the Student-Newman-Keuls Method. A P value of &lt;0.05 was considered statistically significant; n=6-12 per group, *P&lt;0.05 compared to sham. <a href="https://www.jove.com/files/ftp_upload/4289/4289fig3large.jpg" target="_blank"> Click here to view larger figure</a>.
<img alt="Figure 4" src="/files/ftp_upload/4289/4289fig4.jpg" /> 
Figure 4. Evaluation of brain water content following experimental ICH in mice. Intracerebral injection of autologous blood (30 &mu;l) or bacterial collagenase (0.075 U) led to significant increase of brain water content in the ipsilateral cortex and basal ganglia at 24 (A) and 72 hr (B) after ICH-induction. Values were expressed as mean&plusmn;S.E.M. and analyzed with One Way Analysis of Variance, followed by Tukey post hoc test. A P value of &lt;0.05 was considered statistically significant; n=6-10 per group, *P&lt;0.05 compared to sham. <a href="https://www.jove.com/files/ftp_upload/4289/4289fig4large.jpg" target="_blank">Click here to view larger figure</a>.

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	<li>Broderick, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Guidelines+for+the+management+of+spontaneous+intracerebral+hemorrhage:+A+statement+for+healthcare+professionals+from+a+special+writing+group+of+the+Stroke+Council,+American+Heart+Association.">Guidelines for the management of spontaneous intracerebral hemorrhage: A statement for healthcare professionals from a special writing group of the Stroke Council, American Heart Association.</a> Stroke. 30, 905-915 (1999).</li><li>Qureshi, A. I., Mendelow, A. D., Hanley, D. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracerebral+haemorrhage.">Intracerebral haemorrhage.</a> Lancet. 373, 1632-1644 (2009).</li><li>MacLellan, C. L., Silasi, G., Auriat, A. M., Colbourne, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rodent+models+of+intracerebral+hemorrhage.">Rodent models of intracerebral hemorrhage.</a> Stroke. 41, 95-98 (2010).</li><li>James, M. L., Warner, D. S., Laskowitz, D. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preclinical+models+of+intracerebral+hemorrhage:+a+translational+perspective.">Preclinical models of intracerebral hemorrhage: a translational perspective.</a> Neurocrit Care. 9, 139-152 (2008).</li><li>MacLellan, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracerebral+hemorrhage+models+in+rat:+comparing+collagenase+to+blood+infusion.">Intracerebral hemorrhage models in rat: comparing collagenase to blood infusion.</a> J. 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No conflicts of interest declared.

Animal models of intracerebral hemorrhage (ICH) contribute greatly to an advanced understanding of the disease's pathophysiology, and are commonly used to develop and evaluate novel therapeutic strategies in a preclinical setting. Intraparenchymal injections of autologous blood or bacterial collagenase are well-established methods to generate ICH in rodents. Both methods were initially developed in the rat; however, due to the rapidly increasing availability of transgenic and knockout strains, mice became indispensable t...

<table border="1">
 <tbody>
 <tr>
 <td>Material</td>
 <td>Company</td>
 <td>Catalogue 				Number</td>
 <td>Comment</td>
 </tr>
 <tr>
 <td>Stereotactic Head Frame</td>
 <td>Stoelting Co.</td>
 <td>51600</td>
 <td></td>
 </tr>
 <tr>
 <td>Nanomite Syringe Pump</td>
 <td>Harvard Apparatus</td>
 <td>PY2 70-2217</td>
 <td></td>
 </tr>
 <tr>
 <td>Hamilton Syringe</td>
 <td>Hamilton Company</td>
 <td>1725RN 				(250 &mu;l) 
1701 RN (10 &mu;l)</td>
 <td>26 Gauge needle for 				250 &mu;l and 10 &mu;l syringes.</td>
 </tr>
 <tr>
 <td>Microdrill</td>
 <td>Fine Science Tools</td>
 <td>18000-17</td>
 <td></td>
 </tr>
 <tr>
 <td>Microdrill burr</td>
 <td>Fine Science Tools</td>
 <td>19007-09</td>
 <td>0.9 mm diameter</td>
 </tr>
 <tr>
 <td>Collagenase Type VII-S</td>
 <td>Sigma-Aldrich</td>
 <td>C2399</td>
 <td></td>
 </tr>
 <tr>
 <td>Microhematocrit 				Capillary Tubes</td>
 <td>Fisher Scientific</td>
 <td>22-362-574</td>
 <td>unheparinized</td>
 </tr>
 <tr>
 <td>Bone Wax </td>
 <td>Ethicon</td>
 <td>W31</td>
 <td></td>
 </tr>
 <tr>
 <td>Suture</td>
 <td>Ethicon</td>
 <td>1676G</td>
 <td></td>
 </tr>
 <tr>
 <td>Ketamine</td>
 <td>JHP Pharmaceuticals</td>
 <td>42023-115-10</td>
 <td>Ketalar</td>
 </tr>
 <tr>
 <td>Xylazine </td>
 <td>LLOYD Laboratories</td>
 <td>139-236</td>
 <td>AnaSed</td>
 </tr>
 </tbody>
 </table>

modeling intracerebral hemorrhage in mice: injection of autologous blood or bacterial collagenase

Spontaneous intracerebral hemorrhage (ICH) defines a potentially life-threatening neurological malady that accounts for 10-15% of all stroke-related hospitalizations and for which no effective treatments are available to date1,2. Because of the heterogeneity of ICH in humans, various preclinical models are needed to thoroughly explore prospective therapeutic strategies3. Experimental ICH is commonly induced in rodents by intraparenchymal injection of either autologous blood or bacterial collagenase4. The appropriate model is selected based on the pathophysiology of hemorrhage induction and injury progression. The blood injection model mimics a rapidly progressing hemorrhage. Alternatively, bacterial collagenase enzymatically disrupts the basal lamina of brain capillaries, causing an active bleed that generally evolves over several hours5. Resultant perihematomal edema and neurofunctional deficits can be quantified from both models. In this study, we described and evaluated a modified double injection model of autologous whole blood6 as well as an ICH injection model of bacterial collagenase7, both of which target the basal ganglia (corpus striatum) of male CD-1 mice. We assessed neurofunctional deficits and brain edema at 24 and 72 hr after ICH induction. Intrastriatal injection of autologous blood (30 &mu;l) or bacterial collagenase (0.075U) caused reproducible neurofunctional deficits in mice and significantly increased brain edema at 24 and 72 hr after surgery (p&lt;0.05). In conclusion, both models yield consistent hemorrhagic infarcts and represent basic methods for preclinical ICH research.

Watch this Scientific Journal Video about Modeling Intracerebral Hemorrhage in Mice: Injection of Autologous Blood or Bacterial Collagenase at JoVE.com

Modeling Intracerebral Hemorrhage in Mice: Injection of Autologous Blood or Bacterial Collagenase

Clinically relevant animal models of intracerebral hemorrhage (ICH) are needed to extend our knowledge of hemorrhagic stroke and to examine novel therapeutic strategies. In this study, we describe and evaluate two ICH models that implement unilateral injections of either autologous whole blood or bacterial collagenase into the basal ganglia (corpus striatum) of mice.

Spontaneous intracerebral hemorrhage (ICH) defines a potentially life-threatening neurological malady that accounts for 10-15% of all stroke-related ...

modeling-intracerebral-hemorrhage-mice-injection-autologous-blood-or

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24.2K Aufrufe.  Loma Linda University School of Medicine. Klinisch relevante Tiermodelle Hirnblutung (ICH) sind notwendig, um unser Wissen über hämorrhagischen Schlaganfall zu erweitern und neue therapeutische Strategien zu untersuchen. In dieser Studie beschreiben wir und auswerten beiden ICH Modelle einseitige Injektionen von entweder autologe Vollblut oder bakteriellen Collagenase in den Basalganglien (Corpus striatum) von Mäusen implementieren.

Serie: Modeling Intracerebral Hemorrhage in Mice: Injection of Autologous Blood or Bacterial Collagenase

Modeling Stroke in Mice - Middle Cerebral Artery Occlusion with the Filament Model

Stroke is among the most frequent causes of death and adult disability, especially in highly developed countries. However, treatment options to date are very limited. To meet the need for novel therapeutic approaches, experimental stroke research frequently employs rodent models of focal cerebral ischaemia. Most researchers use permanent or transient occlusion of the middle cerebral artery (MCA) in mice or rats.
Proximal occlusion of the middle cerebral artery (MCA) via the intraluminal suture technique (so called filament or suture model) is probably the most frequently used model in experimental stroke research. The intraluminal MCAO model offers the advantage of inducing reproducible transient or permanent ischaemia of the MCA territory in a relatively non-invasive manner. Intraluminal approaches interrupt the blood flow of the entire territory of this artery. Filament occlusion thus arrests flow proximal to the lenticulo-striate arteries, which supply the basal ganglia. Filament occlusion of the MCA results in reproducible lesions in the cortex and striatum and can be either permanent or transient. In contrast, models inducing distal (to the branching of the lenticulo-striate arteries) MCA occlusion typically spare the striatum and primarily involve the neocortex. In addition these models do require craniectomy. In the model demonstrated in this article, a silicon coated filament is introduced into the common carotid artery and advanced along the internal carotid artery into the Circle of Willis, where it blocks the origin of the middle cerebral artery. In patients, occlusions of the middle cerebral artery are among the most common causes of ischaemic stroke. Since varying ischemic intervals can be chosen freely in this model depending on the time point of reperfusion, ischaemic lesions with varying degrees of severity can be produced. Reperfusion by removal of the occluding filament at least partially models the restoration of blood flow after spontaneous or therapeutic (tPA) lysis of a thromboembolic clot in humans.
In this video we will present the basic technique as well as the major pitfalls and confounders which may limit the predictive value of this model.

Filamentous occlusion of the Middle cerebral artery is a common model for studying ischemic stroke in mice.

Stroke is among the most frequent causes of death and adult disability, especially in highly developed countries. However, treatment options to date are ...

Sequencing of Bacterial Microflora in Peripheral Blood: our Experience with HIV-infected Patients

The healthy gastrointestinal tract is physiologically colonized by a large variety of commensal microbes that influence the development 
	of the humoral and cellular mucosal immune system1,2. 
 Microbiota is shielded from the immune system via a strong mucosal barrier. Infections and antibiotics are known to alter both the normal 
	gastrointestinal tract barrier and the composition of resident bacteria, which may result in possible immune abnormalities3.
HIV causes a breach in the gastrointestinal barrier with progressive failure of mucosal immunity and leakage into the systemic circulation of bacterial bioproducts, such as lipopolysaccharide and 
	bacterial DNA fragments, which contribute to systemic immune activation4-7. Microbial translocation is implicated in HIV/AIDS immunopathogenesis and response to therapy 4,8.
We aimed to characterise the composition of bacteria translocating in peripheral blood of HIV-infected patients. To pursue our aim we set up a PCR reaction for the panbacteric 16S ribosomial gene 
	followed by a sequencing analysis.
Briefly, whole blood from both HIV-infected and healthy subjects is used. Given that healthy individuals present normal intestinal homeostasis no translocation of microflora is expected in 
	these patients. Following whole blood collection by venipuncture and plasma separation, DNA is extracted from plasma and used to perform a broad range PCR reaction for the panbacteric 
	16S ribosomial gene9. Following PCR product purification, cloning and sequencing analyses are performed.

Our experiment will show how to perform a sequencing analysis of bacterial species translocating in peripheral blood of HIV positive patients.

The healthy gastrointestinal tract is physiologically colonized by a large variety of commensal microbes that influence the development 
	of the humoral ...

Delivery of Therapeutic Agents Through Intracerebroventricular (ICV) and Intravenous (IV) Injection in Mice

Despite the protective role that blood brain barrier plays in shielding the brain, it limits the access to the central nervous system (CNS) which most often results in failure of potential therapeutics designed for neurodegenerative disorders 1,2. Neurodegenerative diseases such as Spinal Muscular Atrophy (SMA), in which the lower motor neurons are affected, can benefit greatly from introducing the therapeutic agents into the CNS. The purpose of this video is to demonstrate two different injection paradigms to deliver therapeutic materials into neonatal mice soon after birth. One of these methods is injecting directly into cerebral lateral ventricles (Intracerebroventricular) which results in delivery of materials into the CNS through the cerebrospinal fluid 3,4. The second method is a temporal vein injection (intravenous) that can introduce different therapeutics into the circulatory system, leading to systemic delivery including the CNS 5. Widespread transduction of the CNS is achievable if an appropriate viral vector and viral serotype is utilized. Visualization and utilization of the temporal vein for injection is feasible up to postnatal day 6. However, if the delivered material is intended to reach the CNS, these injections should take place while the blood brain barrier is more permeable due to its immature status, preferably prior to postnatal day 2. The fully developed blood brain barrier greatly limits the effectiveness of intravenous delivery. Both delivery systems are simple and effective once the surgical aptitude is achieved. They do not require any extensive surgical devices and can be performed by a single person. However, these techniques are not without challenges. The small size of postnatal day 2 pups and the subsequent small target areas can make the injections difficult to perform and initially challenging to replicate.

Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice

This article demonstrates two very different methods of injection: 1) into the brain (intracerebroventricular) and 2) systemic (intravenous) to introduce the therapeutic agents into the central nervous system of neonatal mice.

Despite the protective role that blood brain barrier plays in shielding the brain, it limits the access to the central nervous system (CNS) which most ...

Assessing Changes in Volatile General Anesthetic Sensitivity of Mice after Local or Systemic Pharmacological Intervention

One desirable endpoint of general anesthesia is the state of unconsciousness, also known as hypnosis. Defining the hypnotic state in animals is less straightforward than it is in human patients. A widely used behavioral surrogate for hypnosis in rodents is the loss of righting reflex (LORR), or the point at which the animal no longer responds to their innate instinct to avoid the vulnerability of dorsal recumbency. We have developed a system to assess LORR in 24 mice simultaneously while carefully controlling for potential confounds, including temperature fluctuations and varying gas flows. These chambers permit reliable assessment of anesthetic sensitivity as measured by latency to return of the righting reflex (RORR) following a fixed anesthetic exposure. Alternatively, using stepwise increases (or decreases) in anesthetic concentration, the chambers also enable determination of a population's sensitivity to induction (or emergence) as measured by EC50 and Hill slope. Finally, the controlled environmental chambers described here can be adapted for a variety of alternative uses, including inhaled delivery of other drugs, toxicology studies, and simultaneous real-time monitoring of vital signs.

Loss of the righting reflex has long served as a standard behavioral surrogate for unconsciousness, also called hypnosis, in laboratory animals. Alterations in volatile anesthetic sensitivity caused by pharmacological interventions can be detected with a carefully controlled high-throughput assessment system, which may be adapted for delivery of any inhaled therapeutic.

One desirable endpoint of general anesthesia is  the state of unconsciousness, also known as hypnosis. Defining the hypnotic state in animals is  less ...

Intravital Video Microscopy Measurements of Retinal Blood Flow in Mice

Alterations in retinal blood flow can contribute to, or be a consequence of, ocular disease and visual dysfunction. Therefore, quantitation of altered perfusion can aid research into the mechanisms of retinal pathologies. Intravital video microscopy of fluorescent tracers can be used to measure vascular diameters and bloodstream velocities of the retinal vasculature, specifically the arterioles branching from the central retinal artery and of the venules leading into the central retinal vein. Blood flow rates can be calculated from the diameters and velocities, with the summation of arteriolar flow, and separately venular flow, providing values of total retinal blood flow. This paper and associated video describe the methods for applying this technique to mice, which includes 1) the preparation of the eye for intravital microscopy of the anesthetized animal, 2) the intravenous infusion of fluorescent microspheres to measure bloodstream velocity, 3) the intravenous infusion of a high molecular weight fluorescent dextran, to aid the microscopic visualization of the retinal microvasculature, 4) the use of a digital microscope camera to obtain videos of the perfused retina, and 5) the use of image processing software to analyze the video. The same techniques can be used for measuring retinal blood flow rates in rats.

Intravital microscopy can be used in animals to visualize and measure retinal vascular diameters, bloodstream velocities, and total retinal blood flow.

Alterations in retinal blood flow can contribute to, or be a consequence of, ocular disease and visual dysfunction. Therefore, quantitation of altered ...

Intrastriatal Injection of Autologous Blood or Clostridial Collagenase as Murine Models of Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a common form of cerebrovascular disease and is associated with significant morbidity and mortality. Lack of effective treatment and failure of large clinical trials aimed at hemostasis and clot removal demonstrate the need for further mechanism-driven investigation of ICH. This research may be performed through the framework provided by preclinical models. Two murine models in popular use include intrastriatal (basal ganglia) injection of either autologous whole blood or clostridial collagenase. Since, each model represents distinctly different pathophysiological features related to ICH, use of a particular model may be selected based on what aspect of the disease is to be studied. For example, autologous blood injection most accurately represents the brain&#39;s response to the presence of intraparenchymal blood, and may most closely replicate lobar hemorrhage. Clostridial collagenase injection most accurately represents the small vessel rupture and hematoma evolution characteristic of deep hemorrhages. Thus, each model results in different hematoma formation, neuroinflammatory response, cerebral edema development, and neurobehavioral outcomes. Robustness of a purported therapeutic intervention can be best assessed using both models. In this protocol, induction of ICH using both models, immediate post-operative demonstration of injury, and early post-operative care techniques are demonstrated. Both models result in reproducible injuries, hematoma volumes, and neurobehavioral deficits. Because of the heterogeneity of human ICH, multiple preclinical models are needed to thoroughly explore pathophysiologic mechanisms and test potential therapeutic strategies.

Preclinical models of intracerebral hemorrhage are utilized to mimic certain aspects of clinical disease. Thus, mechanisms of injury and potential therapeutic strategies may be explored. In this protocol, two models of intracerebral hemorrhage are described, intrastriatal (basal ganglia) injections of autologous blood or collagenase.

Intracerebral hemorrhage (ICH) is a common form of cerebrovascular disease and is associated with significant morbidity and mortality. Lack of effective ...

Modeling Spontaneous Metastatic Renal Cell Carcinoma (mRCC) in Mice Following Nephrectomy

One of the key challenges to improved testing of new experimental therapeutics in renal cell carcinoma (RCC) is the development of models that faithfully recapitulate early- and late-stage metastatic disease progression. Typical tumor implantation models utilize ectopic or orthotopic primary tumor implantation, but few include systemic spontaneous metastatic disease that mimics the clinical setting. This protocol describes the key steps to develop RCC disease progression stages similar to patients. First, it uses a highly metastatic mouse tumor cell line in a syngeneic model to show orthotopic tumor cell implantation. Methods include superficial and internal implantation into the sub-capsular space with cells combined with matrigel to prevent leakage and early spread. Next it describes the procedures for excision of tumor-bearing kidney (nephrectomy), with critical pre- and post- surgical mouse care. Finally, it outlines the steps necessary to monitor and assess micro-and macro-metastatic disease progression, including bioluminescent imaging as well provides a detailed visual necropsy guide to score systemic disease distribution. The goal of this protocol description is to facilitate the widespread use of clinically relevant metastatic RCC models to improve the predictive value of future therapeutic testing.&#160;

Modeling Spontaneous Metastatic Renal Cell Carcinoma mRCC in Mice Following Nephrectomy

Models of spontaneous metastatic renal cell carcinoma (RCC) disease progression can be used for evaluating treatments in a clinically relevant setting. This protocol demonstrates different procedures for orthotopic kidney tumor cell implantation, proper nephrectomy, and finally outlines a necropsy guide for visual and bioluminescent scoring of metastatic burden and localization.

One of the key challenges to improved testing of new experimental therapeutics in renal cell carcinoma (RCC) is the development of models that faithfully ...

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. Experiments involving myocardial injection are currently performed by direct surgical access through a thoracotomy. While convenient when performed at the time of another experimental manipulation such as coronary artery ligation, the need for an invasive procedure for intramyocardial delivery limits potential experimental designs. With ever improving ultrasound resolution and advanced noninvasive imaging modalities, it is now feasible to routinely perform ultrasound-guided, percutaneous intramyocardial injection. This modality efficiently and reliably delivers agents to a targeted region of myocardium. Advantages of this technique include the avoidance of surgical morbidity, the facility to target regions of myocardium selectively under ultrasound guidance, and the opportunity to deliver injectate to the myocardium at multiple, predetermined time intervals. With practiced technique, complications from intramyocardial injection are rare, and mice quickly return to normal activity on recovery from anesthetic. Following the steps outlined in this protocol, the operator with basic echocardiography experience can quickly become competent in this versatile, minimally invasive technique.

Echocardiography-guided percutaneous intramyocardial injection represents an efficient, reliable, and targetable modality for the delivery of gene transfer agents or cells into the murine heart. Following the steps outlined in this protocol, the operator can quickly become competent in this versatile, minimally invasive technique.

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. ...

Modeling Stroke in Mice: Permanent Coagulation of the Distal Middle Cerebral Artery

Stroke is the third most common cause of death and a main cause of acquired adult disability in developed countries. Only very limited therapeutical options are available for a small proportion of stroke patients in the acute phase. Current research is intensively searching for novel therapeutic strategies and is increasingly focusing on the sub-acute and chronic phase after stroke because more patients might be eligible for therapeutic interventions in a prolonged time window. These delayed mechanisms include important pathophysiological pathways such as post-stroke inflammation, angiogenesis, neuronal plasticity and regeneration. In order to analyze these mechanisms and to subsequently evaluate novel drug targets, experimental stroke models with clinical relevance, low mortality and high reproducibility are sought after. Moreover, mice are the smallest mammals in which a focal stroke lesion can be induced and for which a broad spectrum of transgenic models are available. Therefore, we describe here the mouse model of transcranial, permanent coagulation of the middle cerebral artery via electrocoagulation distal of the lenticulostriatal arteries, the so-called &#8220;coagulation model&#8221;. The resulting infarct in this model is located mainly in the cortex; the relative infarct volume in relation to brain size corresponds to the majority of human strokes. Moreover, the model fulfills the above-mentioned criteria of reproducibility and low mortality. In this video we demonstrate the surgical methods of stroke induction in the &#8220;coagulation model&#8221; and report histological and functional analysis tools.

Various murine models of middle cerebral artery occlusion (MCAO) are widely used in experimental brain research. Here, we demonstrate the model of transcranial permanent distal MCAO which produces consistent cortical infarction of a size corresponding to damage imposed by the majority of human ischemic strokes.

Stroke is the third most common cause of death and a main cause of acquired adult disability in developed countries. Only very limited therapeutical ...

The Rabbit Blood-shunt Model for the Study of Acute and Late Sequelae of Subarachnoid Hemorrhage: Technical Aspects

Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and controllable animal models that simulate both conditions are presently uncommon. Therefore, new models are needed in order to mimic human pathophysiological conditions resulting from SAH.
This report describes the technical nuances of a rabbit blood-shunt SAH model that enables control of intracerebral pressure (ICP). An extracorporeal shunt is placed between the arterial system and the subarachnoid space, which enables examiner-independent SAH in a closed cranium. Step-by-step procedural instructions and necessary equipment are described, as well as technical considerations to produce the model with minimal mortality and morbidity. Important details required for successful surgical creation of this robust, simple and consistent ICP-controlled SAH rabbit model are described.

The experimental intracranial pressure-controlled blood shunt subarachnoid hemorrhage (SAH) model in the rabbit combines the standard procedures &#8212; subclavian artery cannulation and transcutaneous cisterna magna puncture, which enables close mimicking of human pathophysiological conditions after SAH. We present step-by-step instructions and discuss key surgical points for successful experimental SAH creation.