Establishment of Acute Pontine Infarction in Rats by Electrical Stimulation

Summary

Presented here is a protocol for establishing acute pontine infarction in a rat model via electrical stimulation with a single pulse.

Abstract

Pontine infarction is the most common stroke subtype in the posterior circulation, while there lacks a rodent model mimicking pontine infarction. Provided here is a protocol for successfully establishing a rat model of acute pontine infarction. Rats weighing about 250 g are used, and a probe with an insulated sheath is injected into the pons using a stereotaxic apparatus. A lesion is produced by the electrical stimulation with a single pulse. The Longa score, Berderson score, and beam balance test are used to assess neurological deficits. Additionally, the adhesive-removal somatosensory test is used to determine sensorimotor function, and the limb placement test is used to evaluate proprioception. MRI scans are then used to assess the infarction in vivo, and TTC staining is used to confirm the infarction in vitro. Here, a successful infarction is identified that is located in the anterolateral basis of the rostral pons. In conclusion, a new method is described to establish an acute pontine infarction rat model.

Introduction

Since the 1980s, the middle cerebral artery occlusion (MCAO) model induced by silicone filaments has been widely used in basic stroke research¹. Other methods (i.e., suturing of one branch of the MCA² and photochemically induced focal infarction) have also been used. These models have been termed MCA-based stroke models and have greatly contributed to investigations of the pathophysiological mechanisms underlying stroke and potential therapeutics. Although there are limitations of these experimental models^3,4, these methods have been used many labs

Protocol

The protocol was reviewed and approved by the Institution Animal Care and Use Committee of The Second Affiliated Hospital of Guangzhou Medical University, an institution accredited by AAALACi. The rats were provided by the Animal Center of Southern Medical University.

1. Animal

1. Use adult male Sprague-Dawley rats weighing 250 ± 10 g.
2. Upon transport, house the rats for at least 1 week before surgery under controlled environmental conditions with an ambient temperature of 25 °C, relative humidity of 65%, and 12 h/12 h light/dark cycle.
3. Provide food and water ad libitum.  

Results

Six animals were subjected to the surgery protocol described above. The control group as shown in the Figure 4 consisted of six rats. The brain slices shown in the Figure 4 were derived from one rat per group.

The MRI scanning showed that the infarction was located in the basis of the pons (Figure 4A). Since the probe was injected 2 mm to the left of the midline, the infarction was located laterally. This.......

Discussion

The present study provides a protocol for generating an acute pontine infarction rat model. This model can be used for research on prognosis and rehabilitation (including post-stroke chronic pain) in pontine stroke patients.

There are several strengths of this method. First, it provides a rat model of acute pontine infarction for future studies. As mentioned above, pontine infarction is a common stroke subtype that has received less attention. A major shortcoming of stroke research has been th.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
4-0 sucture	Shanghai Jinzhong		Surgical instruments
Adhesive tape	Shanghai Jinzhong		Surgical instruments
Animal anesthesia system	RWD		Wear mask when using the system
Bone cement	Shanghai Jinzhong		Surgical instrument
Cured clamp	Shanghai Jinzhong		Surgical instrument
General tissue scissors	Shanghai Jinzhong		Surgical instrument
IndoPhors	Guoyao of China		Sterilization
Isoflurane	RWD	217181101
Lesion Making Device	Shanghai Yuyan		Making a lesion
MRI system	Bruker Biospin		Confirmation of infarction in vivo
Needle holder	Shanghai Jinzhong		Surgical instrument
Penicilin	Guoyao of China		Infection Prevention
Probe	Anke		Need some modification
Q-tips	Shanghai Jinzhong		Surgical instrument
Shearing scissors	Shanghai Jinzhong		Surgical instrument
Stereotaxic apparatus	RWD
Suture needle	Shanghai Jinzhong		Surgical instrument
Tissue holding forcepts	Shanghai Jinzhong		Surgical instrument
TTC	Sigma-Aldrich	BCBW5177	For infarction confirmation in vitro