THC Withdrawal Activated the Same Stress Gene in the Brain as Nicotine and Opiate Withdrawal | Research

The takeaway

Withdrawal from THC induced the Narp gene in the central nucleus of the amygdala, the same brain region and gene response seen during opiate and nicotine withdrawal, suggesting a common molecular component across different drug withdrawals.

Read this if you are interested in the brain changes that occur during drug withdrawal.

Narp gene induced in the amygdala during withdrawal from THC, nicotine, and opiates

What the researchers found

Researchers had previously found that the immediate early gene Narp (which encodes a protein that interacts with AMPA glutamate receptors) is induced in the central nucleus of the amygdala during opiate withdrawal.

This study showed that Narp is also induced in the same brain region during withdrawal from both nicotine and THC.

The central nucleus of the amygdala is known to play a key role in mediating aversive responses to drug withdrawal, responses that are thought to drive continued drug use.

The finding that Narp induction is common across opiate, nicotine, and THC withdrawal suggests it is part of a shared transcriptional response to drug withdrawal rather than being specific to any single substance.

Why it matters

Identifying molecular components shared across different drug withdrawals could lead to treatments that address the unpleasant withdrawal experience regardless of which drug is involved.

The numbers in context

Narp was induced in the central nucleus of the amygdala by withdrawal from three different drug classes: opiates (previously shown), nicotine, and THC.

How the study worked

Animal study examining Narp gene expression in the central nucleus of the amygdala following precipitated withdrawal from chronic nicotine and chronic THC administration in rodents.

What this study cannot tell us

Precipitated withdrawal (using antagonists) rather than spontaneous abstinence was used. Gene expression changes do not necessarily translate to functional significance. The study did not establish whether Narp induction is necessary or sufficient for withdrawal symptoms.

How to read the evidence

Preclinical study identifying a molecular marker. Demonstrates a shared mechanism but does not establish its functional significance in withdrawal symptoms.

When this study was published

Published in 2009. Research on shared molecular mechanisms of drug withdrawal has continued to expand, with AMPA receptor signaling recognized as an important component.

The bigger picture

The idea that different drugs produce withdrawal through partially shared molecular mechanisms supports the concept of addiction as a common brain disease rather than a collection of separate substance-specific disorders.

Questions still open

Could targeting Narp or AMPA receptors reduce withdrawal aversiveness across substances? Is Narp induction correlated with the severity of withdrawal symptoms? Are there additional shared molecular components of withdrawal?

Common questions

What is Narp and why does it matter?

Narp is a gene that produces a protein interacting with AMPA glutamate receptors. Its activation in the amygdala during withdrawal from multiple drugs suggests it may be part of the brain mechanism that makes withdrawal feel unpleasant, which drives continued drug use.

Does this mean THC withdrawal is like opiate withdrawal?

At the molecular level, they share at least one common component (Narp induction in the amygdala). However, the clinical experience is very different in severity. This finding points to shared mechanisms, not identical experiences.

Read the original research

Nicotine and Delta(9)-tetrahydrocannabinol withdrawal induce Narp in the central nucleus of the amygdala.

Synapse (New York, N.Y.), 63(3), 252-5

View on PubMed ↗Publisher’s paper ↗

Citation

Reti, Irving M; Han, Sungho; Miskimon, Matthew; Rosen, Jeffrey B; Baraban, Jay M. (2009). Nicotine and Delta(9)-tetrahydrocannabinol withdrawal induce Narp in the central nucleus of the amygdala.. Synapse (New York, N.Y.), 63(3), 252-5. https://doi.org/10.1002/syn.20586