drawing blood from the penile vein

Estudio comparativo de las técnicas de extracción de sangre en ratas

Blood sampling is necessary for most animal studies, both in vivo and in vitro. In rats, as the frequency and amount of blood sampling can be significant, it is helpful to have different alternatives for collection. Various methods have been described in previous studies.
The most commonly used techniques are tail vein puncture and saphenous vein blood draw. Tail vein sampling is suitable for all rat strains. With proper training, the procedure is simple to perform and causes minimal distress to the animal1. Similarly, the saphenous vein blood draw, provided it is done properly, is also a quick and simple collection method. Neither method requires anesthesia, and both allow for repeated draws of small amounts of blood. However, the saphenous vein puncture usually yields a lower blood volume1 and requires the presence of two people to leave one hindlimb exposed for puncture2.
If large amounts of blood need to be collected from a single animal, cardiac puncture or puncture of the vena cava may be used (up to 10 mL of blood can be drawn from a 150 g rat with cardiac puncture2). These techniques require anesthesia and are terminal procedures. The animal must be euthanized after any of these two techniques2. The jugular stick is an alternative that can be used if large amounts of blood need to be collected in a study that has not yet reached its endpoint. However, this technique also requires significant technical skills to avoid harm to the animal; hence, its use should be limited3.
Other techniques, such as the subclavian vein blood draw, do not need the use of anesthetics before blood collection and allow for repeated sampling of small volumes of blood. However, restrained handling and appropriate needle incision are required for this technique. An improper operation may result in animal pain or even mortality, and the training for this method may be fastidious4. 
Other anecdotal procedures include the orbital puncture and the sublingual vein puncture, both of which require an anesthetic, and neither are recommended nor widely used. Though previous studies have shown faster blood collection by orbital puncture than by tail vein puncture, it was found that orbital puncture under diethyl-ether anesthesia was less well tolerated than the latter method (based on the animals' excitation scores and urine production)5. Moreover, this method is highly influenced by the skill of the person who performs the procedure and is mainly performed by experienced veterinarians. Comparably, the sublingual vein puncture is less distressing and is recommended for repeated blood sampling6. However, this technique presents severe adverse effects such as reduced food and water intake, which can lead to the animal's death7. 
This study describes two methods used in our laboratory for repeated blood sampling. Tail vein puncture can be performed on a conscious animal, and the tissue damage and adverse effects are minimal. The modification of this technique in this study includes stabilizing the tail with the index and middle finger, which allows a single operator to perform the blood collection. The dorsal penile vein puncture has already been described for simple intravenous injections. This technique is performed under anesthesia and allows for a reliable blood source in case of difficulties with other methods (e.g., during the immediate postoperative period, with a small animal, when performing perioperative blood draw under anesthesia). Similar to tail vein sampling, the injury at the puncture site will have a minor overall effect on the animal compared to the techniques mentioned above8. The aim of this methods paper is to offer inexperienced researchers simple and reliable blood sampling alternatives according to the context (e.g., for procedures done under anesthesia, for studies including male rats, for animals with thin tail veins).

Autor destacado: Métodos de recolección de sangre dependientes del contexto en ratas 

Punción modificada de la vena de la cola y la vena del pene para el muestreo de sangre en el modelo de rata

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Drawing Blood from the Penile Vein  

Extracción de sangre de la vena del pene

Mueva el émbolo hacia adelante y hacia atrás en la jeringa varias veces para suavizar la extracción y luego tire del émbolo para crear presión negativa en la jeringa. Retraiga el prepucio de la rata anestesiada del extremo del pene y sostenga las glándulas entre el índice y el pulgar tirando suavemente. La vena dorsal del pene aparecerá como un cordón azul superficial.Con el ojo de la aguja apuntando hacia arriba, inserte la jeringa de insulina en la vena en un ángulo de 35 grados. Una vez que la aguja ha entrado en la vena, la sangre fluirá hacia la jeringa. Extraiga lentamente el émbolo de la jeringa a un ritmo lento y constante para recoger el volumen deseado.Retire la jeringa. Se formará una gota de sangre en el sitio de punción. Aspire la gota para recoger unos microlitros más de sangre en caso de un procedimiento no estéril.Aplique una ligera presión en el sitio de punción para detener el sangrado y limpie el área con una toallita con alcohol nueva. Coloque el pene de nuevo en su posición neutral. Después de apagar el isoflurano, monitoree a la rata hasta que se recupere por completo y devuélvala a su jaula.El volumen de sangre recogido en el método de punción de la vena dorsal del pene bajo anestesia se comparó con la sangre recogida en el método de punción de la vena de la cola con y sin anestesia. El resultado muestra que el método de punción de la vena del pene bajo anestesia y el método de punción de la vena de la cola sin anestesia produjeron cantidades comparables de sangre.

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Drawing Blood from the Penile Vein

2.2K vistas. Mueva el émbolo hacia adelante y hacia atrás en la jeringa varias veces para suavizar la extracción y luego tire del émbolo para crear presión negativa en la jeringa. Retraiga el prepucio de la rata anestesiada del extremo del pene y sostenga las glándulas entre el índice y el pulgar tirando suavemente. La vena dorsal del pene aparecerá como un cordón azul superficial.Con el ojo de la aguja apuntando hacia arriba, inserte la jeringa de insulina en la vena en un ángulo de 35 g...

Video: Drawing Blood from the Penile Vein  

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.

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 ...