Chronic Sleep Deprivation in Mouse Pups by Means of Gentle Handling

Summary

We describe a sleep deprivation technique known as gentle handling where investigators gently prod mice any time sleep behavior is observed. This method is a powerful tool that allows researchers to study the effects that chronic sleep restriction throughout development can have on future brain physiology and behavior.

Abstract

Sleep is critical for proper development and neural plasticity. Moreover, abnormal sleep patterns are characteristic of many neurodevelopmental disorders. Studying how chronic sleep restriction during development can affect adult behavior may add to our understanding of the emergence of behavioral symptoms of neurodevelopmental disorders. While there are many methods that can be used to restrict sleep in rodents including forced locomotion, constant disruption, presentation of an aversive stimulus, or electric shock, many of these methods are very stressful and cannot be used in neonatal mice. Here, we describe gentle handling, a sleep deprivation technique that can be used chronically throughout development and into adulthood to achieve sleep restriction. Gentle handling involves close observation of the mice throughout the sleep deprivation period and requires the researcher to gently prod the animals whenever they are inactive or display behaviors associated with sleep. Coupled with EEG recordings, gentle handling could be used to selectively disrupt a specific phase of sleep such as rapid eye movement (REM) sleep. The technique of gentle handling is a powerful tool for the study of the effects of chronic sleep restriction even in neonatal mice that circumvents many of the more stressful procedures used for sleep deprivation.

Introduction

Sleep plays a critical role in neuronal plasticity and synapse formation and elimination during brain development^1,2. Specifically, rapid eye movement (REM) sleep is essential for forming stable synaptic circuits through both strengthening of specific synapses and synaptic pruning². Pharmacological sleep deprivation early in life leads to many physiological and behavioral deficits^3,4. In addition to pharmacological sleep deprivation, other forms of sleep deprivation such as constant shaking, forced locomotion, or presentation of....

Protocol

NOTE: All the procedures were approved by the National Institute of Mental Health Animal Care and Use Committee and performed in accordance with the National Institutes of Health Guidelines on the Care and Use of Animals.

1. Sleep Deprivation Setup

1. Use soft paintbrushes to gently poke mice when asleep.
   1. Make sure the paintbrush can fit through the bars of the mouse cage feeder to ensure that mice have access to food and water ad libitum during sleep deprivation.
   2. Do not use paintbrushes for multiple cages to prevent the transfer of scents between cages. We suggest that you label each brush with its ....

Results

To investigate the effects of chronic sleep restriction on behavior, we sleep restricted mice for three hours daily between 11:00 AM and 2:00 PM from P5 to P42⁸. Following the sleep restriction, mice were left undisturbed for four weeks and allowed to recover from sleep restriction. Mice were tested for behavior following the four-week recovery period. The three-chamber social behavior test was used to assess sociability (preference for a novel mouse compared to a .......

Discussion

Here we describe a method for sleep deprivation, gentle handling, that can be used in both rodent pups and in adults. Gentle handing requires researchers to observe mice for the duration of a sleep deprivation period and gently prod the animals whenever they are inactive or twitching to prevent sleep. Prior sleep deprivation studies have verified by means of simultaneous electroencephalogram (EEG) recordings that gentle handling prevents both REM and non-REM (NREM) sleep¹⁰. While gentle handling i.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
C57BL/6J mice	Jackson Labs	000664	Wildtype mice used
Super Mouse 750 Mouse Cage	Lab Products, Inc.		Cages for the mice
SANI-Chips Bedding	PJ Murphys		Bedding for the mice
S&S Bristle Brush Assortment Pack	Staples	Item # 13764, Model AB37100	Paint brushes are used to gently poke mice