Moderate Prenatal Alcohol Exposure and Quantification of Social Behavior in Adult Rats

Summary

The goal of the protocol presented here is to describe procedures to expose rats to moderate levels of alcohol during prenatal brain development and to quantify resulting alterations in social behavior during adulthood.

Abstract

Alterations in social behavior are among the major negative consequences observed in children with Fetal Alcohol Spectrum Disorders (FASDs). Several independent laboratories have demonstrated robust alterations in the social behavior of rodents exposed to alcohol during brain development across a wide range of exposure durations, timing, doses, and ages at the time of behavioral quantification. Prior work from this laboratory has identified reliable alterations in specific forms of social interaction following moderate prenatal alcohol exposure (PAE) in the rat that persist well into adulthood, including increased wrestling and decreased investigation. These behavioral alterations have been useful in identifying neural circuits altered by moderate PAE¹, and may hold importance for progressing toward a more complete understanding of the neural bases of PAE-related alterations in social behavior. This paper describes procedures for performing moderate PAE in which rat dams voluntarily consume ethanol or saccharin (control) throughout gestation, and measurement of social behaviors in adult offspring.

Introduction

An estimated 1-5% of children are diagnosed with Fetal Alcohol Spectrum Disorders (FASDs)², which include Fetal Alcohol Syndrome (FAS), partial FAS (pFAS), and Alcohol-Related Neurodevelopmental Disorders (ARNDs)³. Deficits in social behavior and cognition are among the most common adverse outcomes observed in children with FASDs^4-7. Negative consequences are not limited to heavy prenatal alcohol exposure (PAE), as moderate PAE that does not lead to the conspicuous morphological, behavioral and cognitive deficits characteristic of FAS can cause comparatively subtle, but nonetheless persistent, deficits in humans with FASDs^8-10

Protocol

All procedures described here and in the accompanying video have been approved by the Institutional Animal Care and Use Committees of the Health Sciences Center and the main campus of the University of New Mexico.

1. Prenatal Ethanol Exposure

1. Obtain all required materials and chemicals: Saccharin sodium salt hydrate, 190 proof ethanol (95% alcohol by volume), beaded glass drinking tubes , natural rubber white #4 stopper one hole , 1" bend tubes-ball point, paper rulers printed from www.vendian.org/mncharity/dir3/paper_rulers/.
2. Obtain proven adult breeder rats from a vendor or alternative source. Use Long-Evans bree....

Results

Over the course of many breeding rounds female rats in the ethanol condition consistently drink an average of about 2.1 g/kg of ethanol per 4 hr drinking session. Rat dams consume approximately one-half of the four hr total during the first 15 to 30 min after the introduction of the drinking tubes, resulting in a peak maternal serum ethanol concentration of about 60 mg/dl, measured at the 45 min time point. Over the remaining 3.5 hr of the drinking period, they continue to consume 5% ethanol at a lower, but relatively st.......

Discussion

The prenatal alcohol exposure paradigm described here involves voluntary consumption of ethanol (5% v/v) by rat dams during pregnancy. There are a number of protocols for exposing non-human animals to ethanol during brain development represented in the literature, which differ with respect to the timing, dose, duration and route of ethanol administration as well as the species under investigation. Although a thorough treatment of the advantages of various exposure protocols is not provided here, several advantages of the.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Saccharin sodium salt hydrate	Sigma	S1002
190 proof ethanol	Sigma	493538
Beaded glass drinking tubes	Fisher	14-955K
Natural rubber white #4 stopper one hole	Plasticoid	LSG4M181
1" bend tubes-ball point	Ancare	TD-199-3"
Paper rulers	N/A	N/A	www.vendian.org/mncharity/dir3/paper_rulers
Apparatus for social interaction	Custom built	N/A	95 cm X 47 cm X 43 cm
Video cameras	N/A	N/A	Capable of recording low/no light conditions
Infrared illuminators	Vitek	VT-IR1-12
Teklad laboratory grade sani-chips	Harlan	7090A
Brush and dustpan	N/A	N/A
Isopropyl alcohol	Sigma	W292907
Chlorine Dioxide (1.5 mg Tablets)	Quiplabs	N/A	Prepare per manufacturer's recommendation