The authors are grateful to Dr. Ana Cotrim for technical consultation and to Dr. Monzur Murshed for equipment. This work was in part funded by the Canadian Institutes for Health Research.

1. Procedural Description
<ol>
	<li>Subcutaneously inject 1 &mu;l / g body weight of 0.5 mg / ml atropine sulfate monohydrate (Cat# 11330, Fluka, USA) into each mouse to prevent the salivary
	secretions from disrupting the movement of the infusions.</li>
	<li>Anesthetize each mouse with 1 &mu;l / g body weight of a 100 mg / ml ketamine and 20 mg / ml xylazine (Phoenix Scientific, AR, USA) solution 
	injected intra-peritoneal (I.P.)</li>
	<li>Place the mouse on a custom-made plastic platform in the ventral position: the maxillary incisors are locked on a metal wire, and the mandibular incisors are hooked on an elastic string in order to hold the mouth open.</li>
	<li>Use an Insulin syringe with a 29-gauge needle (Cat# 600145, Tyco Healthcare, MA, USA) placed inside a 0.58 mm diameter polyethylene tube (Cat# 427410, Becton 
	Dickinson, MD, USA; Fig 2). The polyethylene tube is inserted 5mm over the tip of a 29-gauge needle. The needle is used as a rigid guide to move the 
	polyethylene tube into the Wharton's duct. The polyethylene tube is inserted 3-5 mm inside the duct. Note that only the polyethylene tube enters the salivary gland 
	duct while the needle remains outside the duct. Inject 50ul of filtered 0.4% trypan blue stain solution (Cat# 15250, Gibco, USA) into the submandibular gland via the 
	Wharton's duct, which is located right beneath the tongue. The infusion is delivered steadily with positive pressure on the syringe piston; the finger remains on the 
	piston even after all of the infusion has been delivered to the gland, in order to prevent a backflow of the infusion intra-orally. The trypan blue solution is used in 
	the video as a dye to demonstrate the technique.</li>
	<li>fter the injection of the trypan blue solution, the mouse was euthanized prior to dissection. The salivary gland is surgically exposed in order to determine 
	how much of the infusions have actually remained in the gland.</li>
</ol>
2. Representative Results:
After the infusions were injected, the mouse was dissected to surgically expose the post-cannulated salivary gland. As shown on Image-2, the dark coloration of the Wharton's duct provides evidence that the trypan blue solution was infused successfully. 
<img src="/files/ftp_upload/3074/3074fig1.jpg" alt="Figure 1" /> 
Figure 1. Cannulation of mouse submandibular gland.
<img src="/files/ftp_upload/3074/3074fig2.jpg" alt="Figure 2" /> 
Figure 2. Polyethylene tube is encased around the tip of a 29-gauge needle. The syringe needle is used as a rigid guide to move the polyethylene tube into the Wharton's duct. The polyethylene tube is inserted (cannulated) 3-5 mm inside the duct. Note that only the polyethylene tube enters the salivary gland duct while the needle remains outside the duct.

<ol>
	<li>Fox, P. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acquired+salivary+dysfunction.+Drugs+and+radiation.">Acquired salivary dysfunction. Drugs and radiation.</a> Ann N Y Acad Sci. 842, 132-137 (1998).</li><li>Bhide, S. A., Miah, A. B., Harrington, K. J., Newbold, K. L., Nutting, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radiation-induced+xerostomia:+pathophysiology,+prevention+and+treatment.">Radiation-induced xerostomia: pathophysiology, prevention and treatment.</a> Clin Oncol (R Coll Radiol). 21, 737-744 (2009).</li><li>Redman, R. S., Ball, W. D., Mezey, E., Key, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dispersed+donor+salivary+gland+cells+are+widely+distributed+in+the+recipient+gland+when+infused+up+the+ductal+tree.">Dispersed donor salivary gland cells are widely distributed in the recipient gland when infused up the ductal tree.</a> Biotech Histochem. 84, 253-260 (2009).</li></ol>

All experiments have been approved by the University Animal Care Committee and were in accordance with the guidelines of the Canadian Council on Animal Care.

A difficulty using this cannulation method is to prevent the backflow of the injected solution. Even if the trypan blue solution has temporarily migrated into the salivary gland successfully, the saliva secretion might interfere with the infusions and cause backflow of the trypan blue solution out of the gland. As a precaution, in addition to using atropine to inhibit secretion of saliva, the polyethylene cannula should remain in the Wharton's duct and the piston of the syringe held for 60 seconds after the infusions hav...

<table border="1">
<tbody>
 <tr>
 <td>Name of the reagent</td>
 <td>Type</td>
 <td>Company</td>
 <td>Catalogue number</td>
 <td>Comments (optional)</td>
 </tr>
 <tr>
 <td>Atropine</td>
 <td>Drug</td>
 <td>Fluka</td>
 <td>11330</td>
 <td>To inhibit saliva secretion</td>
 </tr>
 <tr>
 <td>Ketamine</td>
 <td>Drug</td>
 <td>Phoenix Scientific</td>
 <td>&nbsp;</td>
 <td>Sedation</td>
 </tr>
 <tr>
 <td>Xylazine</td>
 <td>Drug</td>
 <td>Phoenix Scientific</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Polyethylene tubing (0.58 mm diameter) </td>
 <td>Tube</td>
 <td>Intramedic PE-10, Becton Dickinson Diagnostic Systems</td>
 <td>427410</td>
 <td>To insert over tip of needle to avoid tissue injury during insertion into Wharton&#x2019;s duct.</td>
 </tr>
 <tr>
 <td>Ultra Comfort Insulin syringe (with a 29G needle) </td>
 <td>Syringe</td>
 <td>Tyco Healthcare</td>
 <td>600145</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>4% trypan blue </td>
 <td>Stain </td>
 <td>Gibco</td>
 <td>15250 </td>
 <td>&nbsp;</td>
 </tr>
 </tbody>
</table>

cannulation of the mouse submandibular salivary gland via the wharton's duct

Severe salivary gland hypofunction is frequently found in patients with Sj&ouml;gren's syndrome and those who receiving therapeutic 
irradiation in their head and neck regions for cancer treatment. Both groups of patients experience symptoms such as xerostomia (dry mouth), dysphagia 
(impaired chewing and swallowing), severe dental caries, altered taste, oro-pharyngeal infections (candidiasis), mucositis, pain and discomfort.
One innovative approach of regenerative medicine for the treatment of salivary gland hypo-function is speculated in RS Redman, E Mezey 
et al. 2009: stem cells can be directly deposited by cannulation into the gland as a potent method in reviving the functions of the impaired organ. Presumably, 
the migrated foreign stem cells will differentiate into glandular cells to function as part of the host salivary gland. Also, this cannulation technique is an 
expedient and effective delivery method for clinical gene transfer application.
Here we illustrate the steps involved in performing the cannulation procedure on the mouse submandibular salivary gland via the Wharton's duct 
(Fig 1). C3H mice (Charles River, Montreal, QC, Canada) are used for this experiment, which have been kept under clean conventional conditions at 
the McGill University animal resource center. All experiments have been approved by the University Animal Care Committee and were in accordance with the 
guidelines of the Canadian Council on Animal Care.
For this experiment, a trypan blue solution is infused into the gland through the opening of the Wharton's duct using a 
insulin syringe with a 29-gauge needle encased inside a polyethylene tube. Subsequently, the mouse is dissected to show that the infusions migrated 
into the gland successfully.

Watch this Scientific Journal Video about Cannulation of the Mouse Submandibular Salivary Gland via the Wharton's Duct at JoVE.com

Cannulation of the Mouse Submandibular Salivary Gland via the Wharton's Duct

A protocol for the cannulation of the mouse submandibular salivary gland via the Wharton's duct is described. For this experiment, the trypan blue solution is used as a dyer to demonstrate how this technique effectively delivers infusions into the targeted gland, and to suggest the reliability of this new approach as a potential clinical drug/cell therapy for the regeneration of salivary glands.

Severe salivary gland hypofunction is frequently found in patients with Sj&ouml;gren's syndrome and those who receiving therapeutic 
irradiation in their ...

cannulation-mouse-submandibular-salivary-gland-via-wharton-s

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25.9K Views.  McGill University. A protocol for the cannulation of the mouse submandibular salivary gland via the Wharton's duct is described. For this experiment, the trypan blue solution is used as a dyer to demonstrate how this technique effectively delivers infusions into the targeted gland, and to suggest the reliability of this new approach as a potential clinical drug/cell therapy for the regeneration of salivary glands.

Video: Cannulation of the Mouse Submandibular Salivary Gland via the Wharton's Duct

Permanent Cerebral Vessel Occlusion via Double Ligature and Transection

Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow (ischemia) 1. Middle cerebral artery (MCA) delivers a great majority of blood to the lateral surface of the cortex 2, is the most common site of human stroke 3, and ischemia within its territory can result in extensive dysfunction or death 1,4,5. Survivors of ischemic stroke often suffer loss or disruption of motor capabilities, sensory deficits, and infarct. In an effort to capture these key characteristics of stroke, and thereby develop effective treatment, a great deal of emphasis is placed upon animal models of ischemia in MCA.
Here we present a method of permanently occluding a cortical surface blood vessel. We will present this method using an example of a relevant vessel occlusion that models the most common type, location, and outcome of human stroke, permanent middle cerebral artery occlusion (pMCAO). In this model, we surgically expose MCA in the adult rat and subsequently occlude via double ligature and transection of the vessel. This pMCAO blocks the proximal cortical branch of MCA, causing ischemia in all of MCA cortical territory, a large portion of the cortex. This method of occlusion can also be used to occlude more distal portions of cortical vessels in order to achieve more focal ischemia targeting a smaller region of cortex. The primary disadvantages of pMCAO are that the surgical procedure is somewhat invasive as a small craniotomy is required to access MCA, though this results in minimal tissue damage. The primary advantages of this model, however, are: the site of occlusion is well defined, the degree of blood flow reduction is consistent, functional and neurological impairment occurs rapidly, infarct size is consistent, and the high rate of survival allows for long-term chronic assessment.

Permanent Cerebral Vessel Occlusion via Double Ligature and Transection

We describe a highly reproducible method for the permanent occlusion of a rodent major cerebral blood vessel. This technique can be accomplished with very little peripheral damage, minimal blood loss, a high rate of long-term survival, and consistent infarct volume commensurate with the human clinical population.

Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow ...

Technical Aspects of the Mouse Aortocaval Fistula

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.

The goal is to produce an arteriovenous fistula that is simple and reproducible. This method does not use sutures or glue adhesive. Therefore the samples can be used with the least amount of foreign materials for analysis.

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta ...

Collecting Saliva and Measuring Salivary Cortisol and Alpha-amylase in Frail Community Residing Older Adults via Family Caregivers

Salivary measures have emerged in bio-behavioral research that are easy-to-collect, minimally invasive, and relatively inexpensive biologic markers of stress. This article we present the steps for collection and analysis of two salivary assays in research with frail, community residing older adults-salivary cortisol and salivary alpha amylase. The field of salivary bioscience is rapidly advancing and the purpose of this presentation is to provide an update on the developments for investigators interested in integrating these measures into research on aging. Strategies are presented for instructing family caregivers in collecting saliva in the home, and for conducting laboratory analyses of salivary analytes that have demonstrated feasibility, high compliance, and yield quality specimens. The protocol for sample collection includes: (1) consistent use of collection materials; (2) standardized methods that promote adherence and minimize subject burden; and (3) procedures for controlling certain confounding agents. We also provide strategies for laboratory analyses include: (1) saliva handling and processing; (2) salivary cortisol and salivary alpha amylase assay procedures; and (3) analytic considerations.

We demonstrate: (1) procedures for collection of salivary samples in cognitive impaired older adults by family caregivers in the home setting, (2) procedures for measuring stress activity via salivary cortisol and alpha amylase, and (3) representative profiles. Protocols that allow researchers to study stress-linked processes advance our understanding of biological sensitivity and susceptibility.

Salivary measures have emerged in bio-behavioral research  that are easy-to-collect, minimally invasive, and relatively inexpensive  biologic markers of ...

Mouse Kidney Transplantation: Models of Allograft Rejection

Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely replicates both the technical and pathological processes that occur in human renal transplantation. Although mouse models of allogeneic rejection in organs other than the kidney exist, and are more technically feasible, there is evidence that different organs elicit disparate rejection modes and dynamics, for instance the time course of rejection in cardiac and renal allograft differs significantly in certain strain combinations. This model is an attractive tool for many reasons despite its technical challenges. As inbred mouse strain haplotypes are well characterized it is possible to choose donor and recipient combinations to model acute allograft rejection by transplanting across MHC class I and II loci. Conversely by transplanting between strains with similar haplotypes a chronic process can be elicited were the allograft kidney develops interstitial fibrosis and tubular atrophy. We have modified the surgical technique to reduce operating time and improve ease of surgery, however a learning curve still needs to be overcome in order to faithfully replicate the model. This study will provide key points in the surgical procedure and aid the process of establishing this technique.

Here, we present a protocol to study the immunology of rejection. The surgical model presented reports a short operating time and a concise technique. Depending on the donor-recipient strain combination, the transplanted kidney may develop acute cellular rejection or chronic allograft damage, defined by interstitial fibrosis and tubular atrophy.

Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely ...

Surgical Injury to the Mouse Pancreas through Ligation of the Pancreatic Duct as a Model for Endocrine and Exocrine Reprogramming and Proliferation

Expansion of pancreatic beta cells in vivo or ex vivo, or generation of beta cells by differentiation from an embryonic or adult stem cell, can provide new expandable sources of beta cells to alleviate the donor scarcity in human islet transplantation as therapy for diabetes. Although recent advances have been made towards this aim, mechanisms that regulate beta cell expansion and differentiation from a stem/progenitor cell remain to be characterized. Here, we describe a protocol for an injury model in the adult mouse pancreas that can function as a tool to study mechanisms of tissue remodeling and beta cell proliferation and differentiation. Partial duct ligation (PDL) is an experimentally induced injury of the rodent pancreas involving surgical ligation of the main pancreatic duct resulting in an obstruction of drainage of exocrine products out of the tail region of the pancreas. The inflicted damage induces acinar atrophy, immune cell infiltration and severe tissue remodeling. We have previously reported the activation of Neurogenin (Ngn) 3 expressing endogenous progenitor-like cells and an increase in beta cell proliferation after PDL. Therefore, PDL provides a basis to study signals involved in beta cell dynamics and the properties of an endocrine progenitor in adult pancreas. Since, it still remains largely unclear, which factors and pathways contribute to beta cell neogenesis and proliferation in PDL, a standardized protocol for PDL will allow for comparison across laboratories.

This protocol describes an injury model involving the surgical ligation of the pancreatic duct in the adult mouse pancreas, resulting in severe injury that establishes an environment that allows beta cell neogenesis and proliferation. This model can be used as a tool to study mechanisms involved in beta cell formation.

Expansion of pancreatic beta cells in vivo or ex vivo, or generation of beta cells by differentiation from an embryonic or adult stem cell, can provide ...

Retroductal Submandibular Gland Instillation and Localized Fractionated Irradiation in a Rat Model of Salivary Hypofunction

Normal tissues that lie within the portals of radiation are inadvertently damaged. Salivary glands are often injured during head and neck radiotherapy. Irreparable cell damage results in a chronic loss of salivary function that impairs basic oral activities, and increases the risk of oral infections and dental caries. Salivary hypofunction and its complications gravely impact a patient's comfort. Current symptomatic management of the condition is ineffective, and newer therapies to assuage the condition are needed. 
Salivary glands are exocrine glands, which expel their secretions into the mouth via excretory ducts. Cannulation of these ducts provides direct access to the glands. Retroductal delivery of a contrast agent to major salivary glands is a routine out-patient procedure for diagnostic imaging. Using a similar procedure, localized treatment of the glands is feasible. However, performing this technique in preclinical studies with small animals poses unique challenges. In this study we describe the technique of retroductal administration in rat submandibular glands, a procedure that was refined in Dr. Bruce Baum's laboratory (NIH)1, and lay out a procedure for local gland irradiation.

Salivary gland hypofunction, a major adverse effect of head and neck radiotherapy diminishes a patient's quality of life. The demonstration of efficacy of new therapies in animal models is a prerequisite before clinical transition. This protocol describes retroductal administration and local irradiation of rat submandibular glands.

Normal tissues that lie within the portals of radiation are inadvertently damaged. Salivary glands are often injured during head and neck radiotherapy. ...

Pancreatic Duct Infusion: An Effective and Selective Method of Drug and Viral Delivery

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Pancreatic duct infusion is an important technique that can allow for lineage tracing, gene introduction, and cell line-specific targeting. A pancreatic duct infusion technique for drug and viral delivery to pancreatic cells is presented here.

The pancreas is a bifunctional organ with both endocrine and exocrine components. A number of pathologies can afflict the pancreas, including diabetes, ...

Murine Salivary Functional Assessment via Pilocarpine Stimulation Following Fractionated Radiation

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We present a detailed approach to performing saliva collection, including murine tracheostomy and the isolation of three major salivary glands.

Hyposalivation is commonly observed in the autoimmune reaction of Sj&#246;gren's syndrome or following radiation injury to the major salivary glands. In ...

Radiation Treatment of Organotypic Cultures from Submandibular and Parotid Salivary Glands Models Key In Vivo Characteristics

Hyposalivation and xerostomia create chronic oral complications that decrease the quality of life in head and neck cancer patients who are treated with radiotherapy. Experimental approaches to understanding mechanisms of salivary gland dysfunction and restoration have focused on in vivo models, which are handicapped by an inability to systematically screen therapeutic candidates and efficiencies in transfection capability to manipulate specific genes. The purpose of this salivary gland organotypic culture protocol is to evaluate maximal time of culture viability and characterize cellular changes following ex vivo radiation treatment. We utilized immunofluorescent staining and confocal microscopy to determine when specific cell populations and markers are present during a 30-day culture period. In addition, cellular markers previously reported in in vivo radiation models are evaluated in cultures that are irradiated ex vivo. Moving forward, this method is an attractive platform for rapid ex vivo assessment of murine and human salivary gland tissue responses to therapeutic agents that improve salivary function.

Using three-dimensional organotypic cultures to visualize morphology and functional markers of salivary glands may provide novel insights into the mechanisms of tissue damage following radiation. Described here is a protocol to section, culture, irradiate, stain, and image 50&#8211;90 &#956;m thick salivary gland sections prior to and following exposure to ionizing radiation.

Hyposalivation and xerostomia create chronic oral complications that decrease the quality of life in head and neck cancer patients who are treated with ...

A Mouse Model for Chronic Pancreatitis via Bile Duct TNBS Infusion

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. Several rodent models have been developed to study CP, of which the bile duct 2,4,6 -trinitrobenzene sulfonic acid (TNBS) infusion model replicates the features of neuropathic pain seen in CP. However, bile duct drug infusion in mice is technically challenging. This protocol demonstrates the procedure of bile duct TNBS infusion for generation of a CP mouse model. TNBS was infused into the pancreas through the ampulla of Vater in the duodenum. This protocol optimized drug volume, surgical techniques, and drug handling during the procedure. TNBS-treated mice showed features of CP as reflected by bodyweight and pancreas weight reductions, changes in pain-associated behaviors, and abnormal pancreatic morphology. With these improvements, mortality associated with TNBS injection was minimal. This procedure is not only critical in generating pancreatic disease models but is also useful in local pancreatic drug delivery.

Chronic pancreatitis (CP) is a disease characterized by inflammation and fibrosis of the pancreas, often associated with intractable abdominal pain. This article focuses on refining the technique to generate a mouse model of CP via bile duct infusion with 2,4,6 -trinitrobenzene sulfonic acid (TNBS).

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. ...