Prenatal methadone exposure disrupts behavioral development and alters motor neuron intrinsic properties and local circuitry
- Indiana University School of Medicine, United States
- Indiana University, United States
- Indiana University-Purdue University, United States
Abstract
Despite the rising prevalence of methadone treatment in pregnant women with opioid use disorder, the effects of methadone on neurobehavioral development remain unclear. We developed a translational mouse model of prenatal methadone exposure (PME) that resembles the typical pattern of opioid use by pregnant women who first use oxycodone then switch to methadone maintenance pharmacotherapy, and subsequently become pregnant while maintained on methadone. We investigated the effects of PME on physical development, sensorimotor behavior, and motor neuron properties using a multidisciplinary approach of physical, biochemical, and behavioral assessments along with brain slice electrophysiology and in vivo magnetic resonance imaging. Methadone accumulated in the placenta and fetal brain, but methadone levels in offspring dropped rapidly at birth which was associated with symptoms and behaviors consistent with neonatal opioid withdrawal. PME produced substantial impairments in offspring physical growth, activity in an open field, and sensorimotor milestone acquisition. Furthermore, these behavioral alterations were associated with reduced neuronal density in the motor cortex and a disruption in motor neuron intrinsic properties and local circuit connectivity. The present study adds to the limited body of work examining PME by providing a comprehensive, translationally relevant characterization of how PME disrupts offspring physical and neurobehavioral development.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures and tables.
Article and author information
Author details
Funding
National Institute on Alcohol Abuse and Alcoholism (R01AA027214)
- Brady K Atwood
National Institute on Alcohol Abuse and Alcoholism (F30AA028687)
- Gregory G Grecco
National Institute on Alcohol Abuse and Alcoholism (T32AA07462)
- David L Haggerty
- Kaitlin C Reeves
Indiana University
- Bryan K Yamamoto
- Hui-Chen Lu
- Brady K Atwood
Indiana University Health
- Brady K Atwood
IU Simon Cancer Center
- Andrea R Masters
Stark Neurosciences Research Institute
- Gregory G Grecco
- David L Haggerty
- Brady K Atwood
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The animal experimental procedures in this study were approved by the Institutional Animal Care and Use Committee at the Indiana University School of Medicine (Protocol Number 19017). Guidelines set forth by the National Institutes of Health (Maryland, USA) for ethical treatment and care for experimental animals were followed. Whenever possible, we sought to minimize pain and distress of animals. Euthanasia was only performed on mice that were under a deep plane of anesthesia (achieved using isoflurane) which was assessed via the pedal withdrawal reflex.
Copyright
© 2021, Grecco et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Prenatal methadone exposure disrupts behavioral development and alters motor neuron intrinsic properties and local circuitry
eLife 10:e66230.
https://doi.org/10.7554/eLife.66230
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