A subscription to JoVE is required to view this content. Sign in or start your free trial.

Method Article

Burn Injury-Induced Pain and Depression-Like Behavior in Mice

3.2K views

DOI:

10.3791/62817

September 29th, 2021

* These authors contributed equally

In This Article

Summary

A transient scald injury (65 °C ± 0.5 °C, 3 s) of one hind paw decreases the threshold (g) to von Frey filament stimulation of the ipsilateral side and alters gait pattern. Besides, burn injury induces depression-like behavior in the forced swimming test.

Abstract

Scalding water is the most common cause of burn injury in both elderly and young populations. It is one of the major clinical challenges because of the high mortality and sequelae in low- and middle-income countries. Burns frequently induce intense spontaneous pain and persistent allodynia as well as life-threatening problem. More importantly, excessive pain is often accompanied by depression, which may significantly decrease the quality of life. This article shows how to develop an animal model for the study of burn-induced pain and depression-like behavior. After anesthesia, burn injury was induced by dipping one hind paw of the mouse into hot water (65 °C ± 0.5 °C) for 3 s. The von Frey test and automated gait analysis were performed every 2 days after burn injury. In addition, depression-like behavior was examined using the forced swimming test, and the rota-rod test was performed to differentiate the abnormal motor function after burn injury. The main purpose of this study is to describe the development of an animal model for the study of burn injury-induced pain and depression-like behavior in mice.

Introduction

Tissue damage, such as burn and trauma, is generally associated with the co-occurrence of acute pain. Burn injuries and trauma-related symptoms are an estimated 1,80,000 deaths every year are caused by burns-the vast majority occur in low- and middle-income countries from different types of burns1. According to a worldwide report, burns are common in children and account for about 40%-60% of hospitalized patients2,3. These specific injuries are even more serious as they can occur in everyday life, such as boiling or bathing water4,5

Access restricted. Please log in or start a trial to view this content.

Protocol

All experimental protocols were reviewed and approved by the Institutional Animal Care and Use Committee at Chungnam National University in South Korea, and then conducted based on the ethical guidelines of the International Association for the Study of Pain18.

1. Induction of scalding burn injury on the hind paw

  1. House the male ICR mice weighing 20-25 g in a light and temperature-controlled room (12/12 h light-dark cycle, 22.5 °C ± 2.5 °C) with a humidity of 40%-60%.
    NOTE: Both male and female mice can be used for this protocol.
  2. Allow the animal free access....

Access restricted. Please log in or start a trial to view this content.

Results

In order to minimize animal suffering and reduce the number of animals used per the Three Rs (Replacement, Reduction, and Refinement) guidelines, this study was designed with the minimum number of animals for the collection of significant data established through preliminary experiment. In this study, behavioral experiments were independently conducted twice as follows. The gait analysis, mechanical allodynia, and depression-like behavior tests were conducted with Control (n = 5), Burn (n = 7; vehicle control; saline), a.......

Access restricted. Please log in or start a trial to view this content.

Discussion

The scalding burn is a kind of thermal burn that is caused by heated liquids. It has been suggested that first- or second-degree burns occur in most cases, but long-term contact with heat sources can cause third-degree burns26. In the present study, burn injury was induced by exposing the right hind paw of mice into hot water at 65 °C for 3 s4,26. Tissue damage was detected in the burn-injured paw, which shows common symptoms of burns.......

Access restricted. Please log in or start a trial to view this content.

Disclosures

The authors have nothing to disclose.

Acknowledgements

This research was supported by the Chungnam National University and the National Research Foundation of Korea (NRF) grant funded by the government of Korea (NRF-2019R1A6A3A01093963 and NRF-2021R1F1A1062509).

....

Access restricted. Please log in or start a trial to view this content.

Materials

List of materials used in this article
NameCompanyCatalog NumberComments
1 mL syringeBD307809
1.5 mL tubeAxygenMCT-150-C
50 mL tubeSPL50050
Acetaminophen BioXtra, ≥99.0%Sigma-AldrichA7085-100GThis analgesic agent is used as a positive control.
Alfaxan multidose (Alfaxalone)JUROX Pty.LimitedIn this experiment, this material was used for animal anesthesia, and was used as a positive control for experimentally treated drugs in the rota-rod test.
CatWalk automated gait analysis systemNoldusCatWalk XTGait analysis in freely walking rodents is used to study the changes in limb movement and positioning in models with sensory-motor dysfunction
OPTISHIELD (Cyclosporin ophthalmic ointment)Ashish Life ScienceThis material was used for an ointment to prevent corneal drying after induction of anesthesia.
Plexiglass cylinderSCITECH KOREAcustom made productsUsed in forced swimming test
Rota-rod systemSCITECH KOREAAccelerating rota rodUsed in the measurement of Normal Motor Function
von Frey filamentsNorth Coast MedicalNC12775Used in the measurement of Mechanical Allodynia
WaterbathCHANGSHIN SCIENCEC-WBEUsed in the burn injury induction

References

  1. Peck, M. D. Epidemiology of burns throughout the World. Part II: intentional burns in adults. Burns. 38 (5), 630-637 (2012).
  2. Tracy, L. M., Cleland, H. Pain assessment following burn injury in ....

Access restricted. Please log in or start a trial to view this content.

Reprints and Permissions

Tags

Burn Injury ModelPain AssessmentMice Behavioral TestingVon Frey TestGait AnalysisForced Swimming TestRotarod TestMechanical AllodyniaAcetaminophen Treatment