None declared.

This study was approved by the Central South University Ethics Committee for Animal Research from the Second Xiangya Hospital (Changsha, China). The manuscript was prepared according to ARRIVE (Animal Research: Reporting of In Vivo Experiments) guidelines9.
1. Material and Animal Preparation
<ol>
	<li>Prepare required materials: adhesive tape, epilating agent, 75% ethanol, blood collection tube, 2.5 mL syringe connected with needle (24 G, 0.6 mm x 25 mm), hair shaver, electronic scale, and gauge (see Table of Materials).</li>
	<li>Use 20 Sprague-Dawley (SD) rats, aged 8-10 weeks and weighing 153-200 g (see Table of Materials). Maintain rats in accordance with the Guide for the Care and Use of Laboratory Animals10.</li>
	<li>House rats under standard conditions with free access to food and drinking water. Keep them in 530 cm2 cages with wood-shaving bedding (2 rats per cage). Maintain animals in a temperature-controlled room temperature at around 25 &#176;C.</li>
	<li>Induce general anesthesia (sodium pentobarbital 40 mg/kg) in all animals through intraperitoneal injection before the subclavian vein puncture.</li>
	<li>Place the rat in a supine position. Fix the hind limbs in a comfortable position and fix the upper limb parallel to the body axis just beside the trunk. 
	NOTE: No mechanical ventilation is needed for this procedure (Figure 1).</li>
	<li>Clean both sides of the infraclavicular space to remove fur (with hair shaver and epilating agent, see Table of Materials) and any visible dirt. Wipe the neck and thoracic skin with 75% ethanol. Keep the area for puncture clean and dry with gauze.</li>
</ol>
2. Blood Collection Procedure
NOTE: Both sides of the subclavian vein are suitable for puncture, and here we choose the right side for puncture. The location and direction of the right clavicle are identified by the operator&#39;s left thumb (Figure 2). The suprasternal fossae are gently touched with the index finger as the suprasternal fossae is in the direction of the needle (Figure 2).
<ol>
	<li>Rinse a sterile 2.5 mL syringe with heparin solution (10 IU/mL).</li>
	<li>Locate the puncture site 0.5 mm caudal to the outer 1/3 region of the right clavicle (Figure 3). Move the syringe gently into the skin of the puncture site. Once the needle enters the infraclavicular skin, apply negative pressure with the operator&#39;s right hand (Figure 4). 
	NOTE: The average and maximal blood volume are 1.0 mL and 1.4 mL, respectively. The direction of the needle is positioned toward the suprasternal fossae and should be almost parallel to the clavicle just posterior to it. Usually, the subclavian vein can be reached by inserting the needle about 2 mm in this direction. Once the needle enters the vein, blood will enter the syringe under negative pressure.
	<ol>
		<li>Maintain negative pressure until enough volume of blood is drawn (Figure 5).</li>
	</ol>
	</li>
	<li>If the subclavian vein blood collection is not successful, withdraw the needle to the subcutaneous area and adjust the direction of the needle slightly interior to the sternum.
	<ol>
		<li>If three attempts fail, avoid the subclavian vein from the same side and use the contralateral side for blood sampling.</li>
	</ol>
	</li>
	<li>After blood collection, remove the puncture needle, and apply pressure to the puncture site for 1-2 minutes to stop bleeding. 
	NOTE: The pressure must be very gentle to prevent choking.</li>
</ol>
3. Blood Sample Processing
<ol>
	<li>Transfer the blood sample into an anticoagulant-coated vacuum tube (with EDTA) and centrifuge for 10 min at 1600 x g to collect plasma.</li>
	<li>Aspirate the supernatant to a clean tube and store at -80 &#176;C (Figure 6).</li>
</ol>

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This work was supported by the grant from the National Natural Science Foundation of China No. 81670269, No. 81500355 and No. 81500226.

Here, we introduce an alternative method for blood extraction from the subclavian vein and we show that this method is feasible, safe, and applicable for blood sampling in rats. This method is derived from the subclavian vein puncture in pacemaker lead implantation for patients11. The subclavian vein is located just posterior and caudal to the clavicle and is a continuation of the axillary vein. It runs from the outer border of the first rib to the medial border of anterior scalene muscle12. From here, it joins with the internal jugular vein to form the brachiocephalic vein and drains into super vena cava, just beneath suprasternal fossae (Figure 8). The clavicle is easily identified and there is a clear anatomic relationship between the subclavian vein and the clavicle. Here, we applied this clinical skill to animal experiments. Due to the different orientation of the upper limb in humans and rats, the upper limb is placed just beside the trunk during the procedure to expose the space caudal to the clavicle, which will facilitate the puncture (Figure 1).
The subclavian vein is much larger than the tail vein. Therefore, it is easier to get enough blood from the subclavian vein than from the tail vein. The total sample volume could reach 10% of total circulating blood volume each time1. If conventional tail vein blood sampling or another route fails, researchers can consider the subclavian vein puncture. General anesthesia is required for this procedure, and this is a major limitation of this procedure. Here, we use pentobarbital sodium for general anesthesia. Compared to other agents, pentobarbital sodium is easy to inject, and no other special instruments are needed. Tsukamoto et al. reported that isoflurane inhalation had the most stable SpO2 than other agents and had short recovery times. In centers with inhalation equipment, isoflurane can be considered13. Moreover, as the subclavian vein is located near to the thoracic cavity, we must be careful to prevent severe procedure-related complications such as pneumothorax and hemopneumothorax. The direction of the needle must be carefully directed to avoid these complications. Here, the needle is always positioned parallel to the clavicle and just posterior to it and moved gently towards the suprasternal fossae. The results show that use of above technique can avoid potential complications. Avoid any downward direction of the needle toward the thoracic cavity in this procedure. Also, the depth of the subclavian vein must always be kept about 2 mm from the puncture site.
Occasionally, attempts from one side may fail. We do not suggest more than 3 attempts from the same side. In such conditions, use the other side for puncture, which may improve the success rate of blood sampling. To further illustrate the feasibility of our method, we tested the success rate and time expended between a beginner group and a skilled group. Interestingly, there were no statistical significance between these groups (p = 0.33), which proved the practicability of this newly developed method.
As discussed here, the main limitation is the success rate on one side. If the procedure fails, the other side of the subclavian vein must be considered. General anesthesia is used in this procedure and the recovery time averaged about 30 min with pentobarbital sodium. Isoflurane inhalation anesthesia has a much shorter recovery time and the adoption of new anesthesia methods could be helpful in reducing the duration of the procedure. We show that this method is applicable to rats, but we have not tested its applicability to smaller animals such as mice.
In conclusion, the study results indicate that the subclavian vein puncture method for blood sample collection is safe and feasible in rats. This method is especially valuable when large amounts of blood are needed. This method is an optimal alternative if conventional blood sampling procedures fail.

Blood collection is essential in animal research. The target veins for blood collection include the retro-orbital plexus, the jugular vein, the saphenous vein, tail blood vessels, and the carotid artery1,2,3,4. Sometimes, blood could be obtained from the abdominal aorta, vena cava or even the heart5,6,7. On such occasions, the animals must be sacrificed and cannot be used for subsequent observation; thus, these methods are used less in daily experimental work. Blood collection from the tail vein of rats is popular and less stressful compared to the above mentioned methods8.
However, blood collection from the tail vein is sometimes limited by an unsatisfactory success rate. Occasionally, it is also difficult to obtain enough blood volume by this method. As the subclavian vein is large enough and is located just under the clavicle bone, subclavian vein puncture can be an alternative method for blood sampling if routine blood collection methods are unsuccessful. Here, we introduce a method of blood collection by means of subclavian vein puncture in rats.

<table><tbody><tr><td>rats</td><td>Hunan SJA Laboratory Animal Co., Ltd (Changsha, Hunan Province, China)&amp;nbsp;</td><td></td><td></td></tr><tr><td>stastical software</td><td>SPSS Statistics 17</td><td></td><td></td></tr><tr><td>epilating agent</td><td>France Yi Sha Cosmetics Co.,Ltd(Guangzhou, Guangdong Province ,China)</td><td></td><td></td></tr><tr><td>2.5 mL syringe</td><td>Shandong Weigao Group Medical Polymer Co.,Ltd(Weihai,Shandong Province ,China)</td><td></td><td></td></tr><tr><td>hair shaver</td><td>Shanghai FLYCO Electric Co., Ltd(Shanghai,China)</td><td></td><td></td></tr><tr><td>adhesive tape</td><td>3M Deutschland GmbH(EdisonstraBe 6,59157 Kamen, Germany)</td><td></td><td></td></tr><tr><td>Pentobarbital sodium</td><td>Merck</td><td></td><td></td></tr><tr><td>75% ethanol</td><td>Department of Pharmacy,The Second Xiangya Hospital of Central South Univesity</td><td></td><td></td></tr><tr><td>blood collection tube</td><td>Hubei Jinxing Technology&amp;amp;Development Co.,Ltd (Wuhan Hubei Province,China) (2ml)</td><td></td><td></td></tr><tr><td>electronic scale</td><td>Dongguan Shengheng Electronics Co.,Ltd (Dongguan,Guangdng Province,China)</td><td></td><td></td></tr><tr><td>canvas gloves</td><td>for anethesia</td><td></td><td></td></tr><tr><td>hepain</td><td>Nanjing Xinbai Pharmaceutical&amp;nbsp; Co.,Limited (Nanjing, Jiangsu Province, China) (2mL, 12500 IU)</td><td></td><td></td></tr><tr><td>physical saline</td><td>Hunan Kelun Pharmaceutical Co., Ltd(Yueyang ,Hunan Province,China) (100ml)</td><td></td><td></td></tr></tbody></table>

subclavian vein puncture as an alternative method of blood sample collection in rats

Blood collection with enough blood volume is essential in animal experiments. Blood collection from the tail vein of rats is popular and less stressful compared to other more aggressive methods such as retro-orbital plexus sample collection. However, this blood collection method is sometimes limited by an unsatisfactory success rate. Here, we introduce a method for blood collection through the subclavian vein puncture. The subclavian vein is located just under the clavicle and this vein is large enough to fulfill the volume requirements of blood collection. Our results show that this method is safe and applicable for blood collection sampling with the required blood volume. Blood collection through the subclavian vein puncture could serve as an alternative blood collection method in case of failed tail vein blood sampling in rats.

A total of 20 SD rats (male n=10, female n=10) were used here.&#160;Blood collectionwas performed by skilled operators, who have performed more than 20 blood samplings from the subclavian vein in rats, and by the beginner operators, who have no subclavian vein puncture experience in rats or other animals. Before operations, beginners watched at least 3 procedures done by skilled operators.
Blood sampling succeeded in 17 rats through the right subclavian vein access. This procedure failed in 3 rats (1 in the skilled group and 2 in the beginner group), and blood sampling was successful through the left subclavian vein accesses in these 3 rats. The time course and blood volume collected for each case are illustrated in Table 1. The success rate was similar between the beginner group (80%) and the skilled group (90%, p = 0.531). The success rate was 100% for both groups when including the additional left subclavian vein accesses in the 3 rats. Two tailed Student&#39;s t-test showed that there was no significant difference on time expended between beginner group and skilled group (102.1 &#177; 14.9 s versus 84.3 &#177; 9.7 s, p = 0.33, Figure 7). No severe complications occurred in all procedures such as pneumothorax, hemopneumothorax, or major bleeding during or after operation. All animals survived and recovered within 30 minutes after the blood sampling.
To demonstrate the difficulties of learning the puncture procedure, we further compared the number of withdrawals between skilled and beginner groups. As shown in Table 2, the average number of withdrawals in the skilled group is slightly less than the beginner group (1.6 &#177;0.3 vs. 2.5 &#177;0.4), but there is no statistical significance (p = 0.0913).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/58499/58499fig1.jpg" /> 
Figure 1: Position of rats. The rats are laid in a supine position, and the upper limbs are fixed parallel to the body axis, just beside the trunk. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/58499/58499fig2.jpg" /> 
Figure 2: Identify the surface symbols of rats. (A) The left thumb of the operator is on the right clavicle to identify the location and array of this bone; (B) The suprasternal fossae are gently touched with the index finger. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/58499/58499fig3.jpg" /> 
Figure 3: Location of puncture. The puncture site is located 0.5 mm caudal to the outer 1/3 site of the right clavicle. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/58499/58499fig4.jpg" /> 
Figure 4: Forming negative pressure in the syringe. Once the needle enters the infraclavicular skin, the fingers of right hand move to create negative pressure in the syringe. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/58499/58499fig5.jpg" /> 
Figure 5: Withdrawing blood into the syringe. When the needle enters the subclavian vein, blood will enter the syringe under negative pressure. The negative pressure is kept until enough blood is obtained. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig5large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 6" class="xfigimg" src="/files/ftp_upload/58499/58499fig6.jpg" /> 
Figure 6: Plasma extraction after centrifuging. After centrifuging, the blood is separated into plasma and cells. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig6large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 7" class="xfigimg" src="/files/ftp_upload/58499/58499fig7.jpg" /> 
Figure 7: The time course and success rate between different groups. This chart shows no significant differences in the time spent (left panel) or success rate (right panel) between the skilled group and the beginner group. The time course in the beginner group and the skilled group are 102.1 &#177; 14.9 s and 84.3 &#177; 9.7 s, respectively, p = 0.33 between groups. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig7large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 8" class="xfigimg" src="/files/ftp_upload/58499/58499fig8.jpg" /> 
Figure 8: The anatomy of subclavian vein. The subclavian vein is located just posterior and caudal to the clavicle. It joins with the internal jugular vein to form the brachiocephalic vein and drains into super vena cava, just beneath the suprasternal fossae. <a href="https://www.jove.com/files/ftp_upload/58499/58499fig8large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td colspan="5">skilled group</td>
			<td></td>
			<td colspan="5">Beginner group</td>
		</tr>
		<tr>
			<td></td>
			<td>Gender</td>
			<td>Body weight (g)</td>
			<td>Blood volume (mL)</td>
			<td>Time course (S)</td>
			<td></td>
			<td></td>
			<td>Gender</td>
			<td>Body weight (g)</td>
			<td>blood volume (mL)</td>
			<td>Time course (S)</td>
		</tr>
		<tr>
			<td>S1</td>
			<td>male</td>
			<td>153</td>
			<td>1.6</td>
			<td>70</td>
			<td></td>
			<td>B1</td>
			<td>male</td>
			<td>149</td>
			<td>1.6</td>
			<td>72</td>
		</tr>
		<tr>
			<td>S2</td>
			<td>male</td>
			<td>168</td>
			<td>1.6</td>
			<td>60</td>
			<td></td>
			<td>B2</td>
			<td>male</td>
			<td>158</td>
			<td>1.6</td>
			<td>68</td>
		</tr>
		<tr>
			<td>S3</td>
			<td>female</td>
			<td>183</td>
			<td>1.6</td>
			<td>75</td>
			<td></td>
			<td>B3</td>
			<td>female</td>
			<td>190</td>
			<td>1.6</td>
			<td>83</td>
		</tr>
		<tr>
			<td>S4</td>
			<td>female</td>
			<td>170</td>
			<td>1.6</td>
			<td>74</td>
			<td></td>
			<td>B4</td>
			<td>female</td>
			<td>160</td>
			<td>1.6</td>
			<td>77</td>
		</tr>
		<tr>
			<td>S5</td>
			<td>female</td>
			<td>159</td>
			<td>1.6</td>
			<td>65</td>
			<td></td>
			<td>B5</td>
			<td>female</td>
			<td>153</td>
			<td>1.6</td>
			<td>200</td>
		</tr>
		<tr>
			<td>S6</td>
			<td>male</td>
			<td>200</td>
			<td>1.6</td>
			<td>83</td>
			<td></td>
			<td>B6</td>
			<td>male</td>
			<td>187</td>
			<td>1.6</td>
			<td>92</td>
		</tr>
		<tr>
			<td>S7</td>
			<td>male</td>
			<td>178</td>
			<td>1.6</td>
			<td>86</td>
			<td></td>
			<td>B7</td>
			<td>male</td>
			<td>164</td>
			<td>1.6</td>
			<td>99</td>
		</tr>
		<tr>
			<td>S8</td>
			<td>male</td>
			<td>187</td>
			<td>1.6</td>
			<td>168</td>
			<td></td>
			<td>B8</td>
			<td>male</td>
			<td>200</td>
			<td>1.6</td>
			<td>82</td>
		</tr>
		<tr>
			<td>S9</td>
			<td>female</td>
			<td>192</td>
			<td>1.6</td>
			<td>83</td>
			<td></td>
			<td>B9</td>
			<td>female</td>
			<td>198</td>
			<td>1.6</td>
			<td>70</td>
		</tr>
		<tr>
			<td>S10</td>
			<td>female</td>
			<td>157</td>
			<td>1.6</td>
			<td>79</td>
			<td></td>
			<td>B10</td>
			<td>female</td>
			<td>175</td>
			<td>1.6</td>
			<td>178</td>
		</tr>
	</tbody>
</table>
Table 1: The blood volume and time course from puncture to a finished blood collection. S: skilled group; B: beginners.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Group&#160;</td>
			<td>n</td>
			<td>Mean</td>
			<td>SE</td>
			<td colspan="2">95% Conf. Interval</td>
		</tr>
		<tr>
			<td>B</td>
			<td>10</td>
			<td>2.5</td>
			<td>0.4</td>
			<td>1.59</td>
			<td>3.41</td>
		</tr>
		<tr>
			<td>S</td>
			<td>10</td>
			<td>1.6</td>
			<td>0.3</td>
			<td>0.91</td>
			<td>2.29</td>
		</tr>
	</tbody>
</table>
Table 2: The number of withdrawals between the two groups. B: beginners; S: skilled group. p = 0.0913

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Subclavian Vein Puncture As an Alternative Method of Blood Sample Collection in Rats

Here, we present a protocol to collect blood samples from the rat subclavian vein.

Blood collection with enough blood volume is essential in animal experiments. Blood collection from the tail vein of rats is popular and less stressful ...

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Universidad San Sebastian

Research

JoVE Journal

Medicine

13.9K Views.  Central South University. Subclavian Vein Punctie als alternatieve methode van bloedmonsterverzameling bij ratten. Na algemene anesthesie, plaats ratten in supine positie en steriliseren infraclaviculaire ruimte met 75%ethanol. Identificeer superieure sternale fossa voor punctie.Zoek de punctieplaats, caudal naar het buitenste een derde gebied van het sleutelbeen aan dezelfde kant. De richting van de naald werd geplaatst in de richting van de superieure sternale fossa en moet bijna parallel aan het sleutelbeen,...

Video: Subclavian Vein Puncture As an Alternative Method of Blood Sample Collection in Rats

Drawing Blood from Rats through the Saphenous Vein and by Cardiac Puncture

Drawing blood from rodents is necessary for a large number of both in vitro and in vivo studies. Sites of blood draws are numerous in rodents: retro-orbital sinus, jugular vein, maxillary vein, saphenous vein, heart. Each technique has its advantages and disadvantages, and some are not approved any more in some countries (e.g., retro-orbital draws in Holland). A discussion of different techniques for drawing blood are available 1-3.
Here, we present two techniques for drawing blood from rats, each with its specific applications.
Blood draw from the saphenous vein, provided it is done properly, induces minimal distress in animals and does not require anesthesia. This technique allows repeated draws of small amounts of blood, such as needed for pharmacokinetic studies 4,5, determining plasma chemistry, or blood counts 6.
Cardiac puncture allows the collection of large amounts of blood from a single animal (up to 10 ml of blood can be drawn from a 150 g rat). This technique is therefore very useful as a terminal procedure when drawing blood from the saphenous would not provide a large enough sample. We use cardiac puncture when we need sufficient amounts of serum from a specific strain of rats to grow T lymphocyte lines in vitro 4-9.

Blood draws are necessary in a large number of studies, for example to study the pharmacokinetics profile of a compound. Here, we demonstrate how to draw blood from rats using two techniques: blood draw from the saphenous vein or by cardiac puncture.

Drawing blood from rodents is necessary for a large number of both in vitro and in vivo studies. Sites of blood draws are numerous in rodents: ...

Biology

Automated Measurement of Microcirculatory Blood Flow Velocity in Pulmonary Metastases of Rats

Because the lung is a major target organ of metastatic disease, animal models to study the physiology of pulmonary metastases are of great importance. However, very few methods exist to date to investigate lung metastases in a dynamic fashion at the microcirculatory level, due to the difficulty to access the lung with a microscope. Here, an intravital microscopy method is presented to functionally image and quantify the microcirculation of superficial pulmonary metastases in rats, using a closed-chest pulmonary window and automated analysis of blood flow velocity and direction. The utility of this method is demonstrated to measure increases in blood flow velocity in response to pharmacological intervention, and to image the well-known tortuous vasculature of solid tumors. This is the first demonstration of intravital microscopy on pulmonary metastases in a closed-chest model. Because of its minimized invasiveness, as well as due to its relative ease and practicality, this technology has the potential to experience widespread use in laboratories that specialize on pulmonary tumor research.

A method is presented to measure microcirculatory blood flow velocity in pulmonary cancer metastases of the pleural surface in rats in an automated fashion, using closed-chest pulmonary intravital microscopy. This model has potential to be used as a widespread tool to perform physiologic research on pulmonary metastases in rodents.

Because the lung is a major target organ of metastatic disease, animal models to study the physiology of pulmonary metastases are of great importance. ...

Sublingual Immunotherapy as an Alternative to Induce Protection Against Acute Respiratory Infections

Sublingual route has been widely used to deliver small molecules into the bloodstream and to modulate the immune response at different sites. It has been shown to effectively induce humoral and cellular responses at systemic and mucosal sites, namely the lungs and urogenital tract. Sublingual vaccination can promote protection against infections at the lower and upper respiratory tract; it can also promote tolerance to allergens and ameliorate asthma symptoms. Modulation of lung&#8217;s immune response by sublingual immunotherapy (SLIT) is safer than direct administration of formulations by intranasal route because it does not require delivery of potentially harmful molecules directly into the airways. In contrast to intranasal delivery, side effects involving brain toxicity or facial paralysis are not promoted by SLIT. The immune mechanisms underlying SLIT remain elusive and its use for the treatment of acute lung infections has not yet been explored. Thus, development of appropriate animal models of SLIT is needed to further explore its potential advantages. 
This work shows how to perform sublingual administration of therapeutic agents in mice to evaluate their ability to protect against acute pneumococcal pneumonia. Technical aspects of mouse handling during sublingual inoculation, precise identification of sublingual mucosa, draining lymph nodes and isolation of tissues, bronchoalveolar lavage and lungs are illustrated. Protocols for single cell suspension preparation for FACS analysis are described in detail. Other downstream applications for the analysis of the immune response are discussed. Technical aspects of the preparation of Streptococcus pneumoniae inoculum and intranasal challenge of mice are also explained.
SLIT is a simple technique that allows screening of candidate molecules to modulate lungs&#8217; immune response. Parameters affecting the success of SLIT are related to molecular size, susceptibility to degradation and stability of highly concentrated formulations.

The present work illustrates the convenience of using sublingual immunotherapy to boost the innate immune response in the lungs and confer protection against acute pneumococcal pneumonia in mouse.

Sublingual route has been widely used to deliver small molecules into the bloodstream and to modulate the immune response at different sites. It has been ...

An Improved Method for Rapid Intubation of the Trachea in Mice

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity is a commonly used model to study both acute lung injury and fibrosis, and multiple methods have been developed for administering bleomycin (and other toxic agents) into the lungs. However, many of these approaches, such as transtracheal instillation, have inherent drawbacks, including the need for strong anesthetics and survival surgery. This paper reports a quick, reproducible method of intratracheal intubation that involves mild inhaled anesthesia, visualization of the trachea, and the use of a surrogate spirometer to confirm exposure. As a proof of concept, 8-12 week old C57BL/6 mice were administered either 2.0 U/kg of bleomycin or an equivalent volume of PBS, and both damage and fibrotic endpoints were measured post-exposure. This procedure allows researchers to treat a large cohort of mice in a relatively short period with little expense and minimal post-procedure care.

This article presents a rapid and simple method for administering bleomycin directly into the mouse trachea via intubation. Key advantages of this method are that it is highly reproducible, easy to master, and does not require specialized equipment or lengthy recovery times.

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity ...

Repeated Blood Collection from Tail Vein of Non-Anesthetized Rats with a Vacuum Blood Collection System

Blood can be collected from rats in a number of sampling locations. For instance, the tail vein is a superior location for blood sampling. However, the tail vein is thin so that it is sometimes hard to puncture. In addition, the tail vein has low blood flow and requires a long sampling time to get sufficient blood. The present report describes a simple blood sampling method, the vacuum blood collection method, which is usually used to obtain blood samples from patients, here used for non-anesthetized rats. The 22 G butterfly needle tip was inserted into one of the lateral tail veins approximately 2-3 cm from the tip of the tail at an angle of approximately 20&#176;, and blood was collected in the vacuum collection tube by inserting the rubber end of the butterfly needle into the vacuum blood collection tube. The present experimental results show that the success rate was 95% in the experimental group and 90% in the beginner group. The success rate and puncture times were similar between two groups. The sampling duration was significantly shorter in the experimental group compared to beginner group. In conclusion, this vacuum blood collection method for sequential blood sampling from the tail vein of non- anesthetized rats is feasible and easy-to-learn, which might serve as a reliable alternative to other conventionally used blood sampling techniques for rats.

Here, we describe a simple tail vein blood sampling method in non-anesthetized rats using a vacuum extraction tube system. This method reduces the risk of direct exposure to blood and simplifies taking multiple samples from a single venipuncture.

Blood can be collected from rats in a number of sampling locations. For instance, the tail vein is a superior location for blood sampling. However, the ...

Blood Collection Through Subclavian Vein Puncture in Mice

The mouse is the foremost mammalian model for studying human disease and human health. However, blood sample collection from mice is challenging in research work. Tail blood collection is a popular method when a small amount of blood sample is needed. Orbital artery could be considered if a large amount of blood is needed but this blood collection method has ethical issues. Formerly, we demonstrated the feasibility and safety of blood sample collection through subclavian vein puncture in rats, and here we investigate whether this method could be used in mice. We report that this method is safe and practical for blood collection in mice. Blood collection through the subclavian vein puncture in mice can be a convenient method in daily research works.

Here, we present a protocol to take blood samples from the subclavian vein of mice.

The mouse is the foremost mammalian model for studying human disease and human health. However, blood sample collection from mice is challenging in ...

Sampling Blood from the Lateral Tail Vein of the Rat

Blood samples are commonly obtained in many experimental contexts to measure targets of interest, including hormones, immune factors, growth factors, proteins, and glucose, yet the composition of the blood is dynamically regulated and easily perturbed. One factor that can change the blood composition is the stress response triggered by the sampling procedure, which can contribute to variability in the measures of interest. Here we describe a procedure for blood sampling from the lateral tail vein in the rat. This procedure offers significant advantages over other more commonly used techniques. It permits rapid sampling with minimal pain or invasiveness, without anesthesia or analgesia. Additionally, it can be used to obtain large volume samples (upwards of 1 ml in some rats), and it may be used repeatedly across experimental days. By minimizing the stress response and pain resulting from blood sampling, measures can more accurately reflect the true basal state of the animal, with minimal influence from the sampling procedure itself.

Blood samples are useful for assessing biomarkers of physiological states or disease in vivo. Here we describe the methodology to sample blood from the lateral tail vein in the rat. This method provides rapid samples with minimal pain and invasiveness.

Blood samples are commonly obtained in many experimental contexts to measure targets of interest, including hormones, immune factors, growth factors, ...

Repetitive Blood Sampling from the Subclavian Vein of Conscious Rat

Rats are widely used in pharmacokinetics (PK) and toxicokinetic (TK) studies that need to collect a certain amount of blood at specific time points to detect drug exposure. The rat blood sampling method determines the quality of the plasma and further affects the precision of the test results. The subclavian vein blood collection method described in this protocol collects blood samples repeatedly in the conscious state of animals to meet the needs of PK and TK tests. The skills of restraint handling and appropriate procedure of needle incision ensure the success rate of blood collection. It is easy to operate while ensuring the quality of plasma and at the same time catering to animal welfare. However, this method requires skilled operation, and an improper one may cause animal weakness, pain, lameness, and even mortality. The current method has been used in the testing facility for a 4-week oral toxicity study in Sprague Dawley (SD) rats with TK. The maximum amount of blood collected within 24 h did not exceed 20% of the animal's total blood. The animals' body weight was more than 200 g for males and females. The data showed that the animals' bodyweight increased steadily every week, and the clinical observation was normal after repetitive sample collection.

The present protocol describes a simple and efficient method for collecting blood from the subclavian vein in rats. It enables rapid, timely, and easily identifiable sampling without anesthesia and obtains high-quality blood through repetitive sample collection.

Rats are widely used in pharmacokinetics (PK) and toxicokinetic (TK) studies that need to collect a certain amount of blood at specific time points to ...

Comparative Study of Blood Collection Techniques in Rats

Modified Tail Vein and Penile Vein Puncture for Blood Sampling in the Rat Model

Blood samples are required in most experimental animal designs to assess various hematological parameters. This paper presents two procedures for blood collection in rats: the lateral tail vein puncture and the dorsal penile vein puncture, which offer significant advantages over other previously described techniques. This study shows that these two procedures allow for fast sampling (under 10 min) and yield sufficient blood volumes for most assays (202 &#956;L &#177; 67.7 &#956;L). The dorsal penile vein puncture must be done under anesthesia, whereas the lateral tail vein puncture can be done on a conscious, restrained animal.
Alternating these two techniques, therefore, enables blood draw in any situation. While it is always recommended for an operator to be assisted during a procedure to ensure animal welfare, these techniques require only a single operator, unlike most blood sampling methods that require two. Moreover, whereas these previously described methods (e.g., jugular stick, subclavian vein blood draw) require extensive prior training to avoid harm to or death of the animal, tail vein and dorsal penile vein puncture are rarely fatal. For all these reasons, and according to the context (e.g., for studies including male rats, during the perioperative or immediate postoperative period, for animals with thin tail veins), both techniques can be used alternately to enable repeated blood draws.

Author Spotlight: Context Dependent Blood Collection Methods in Rats 

Here, we present a protocol to offer rapid, easy, and reliable blood collection alternatives for the rat model. We describe three different blood sampling methods according to the context: tail vein puncture under anesthesia or on a conscious animal, and dorsal penile vein puncture under anesthesia.

Blood samples are required in most experimental animal designs to assess various hematological parameters. This paper presents two procedures for blood ...

Subclavian Vein Puncture Method for Repeated Blood Collection in Conscious Rats

Subclavian Vein Blood Sampling in Conscious Rats

There are several established methods for obtaining repeated blood samples from rats, with the most commonly employed methods being lateral tail vein sampling without anesthesia and jugular vein sampling with anesthesia. However, most of these methods require assistance and anesthetic equipment and sometimes pose difficulties in terms of blood collection or the poor quality of blood samples. In addition, these methods of blood collection consume significant time and human resources when repeated blood sampling is required for a large number of rats. This study presents a technique for repetitive blood sampling in non-anesthetized rats by a single proficient individual. Highly satisfactory blood samples can be obtained by puncturing the subclavian vein. The method demonstrated an impressive overall success rate of 95%, with a median time of merely 2 min from rat restraint to the completion of blood collection. Furthermore, performing consecutive blood collections within the designated range does not inflict any harm on the rats. This method is worth promoting for blood collection, especially in large-scale pharmacokinetic studies.

Author Spotlight: Developing an Efficient Blood Collection Method in Non-Anesthetized Rats 

Here we present a combination of effective rat restriction and subclavian vein puncture methods that enable rapid, safe, and repeated blood collection in rats without anesthesia.

There are several established methods for obtaining repeated blood samples from rats, with the most commonly employed methods being lateral tail vein ...

Subclavian Vein Puncture As an Alternative Method of Blood Sample Collection in Rats

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