Boosting the Brain's Own Cannabis-Like Chemical Anandamide Reduced Panic-Like Behavior in Mice | Research

The takeaway

Increasing anandamide levels in mice reduced panic-like flight responses to a threatening stimulus, while boosting 2-AG had the opposite effect.

Read this if you are interested in how the brain's own cannabis-like chemicals relate to anxiety and panic responses.

Anandamide enhancement reduced panic-like flight; 2-AG enhancement increased it

What the researchers found

Using a novel behavioral task that confronted mice with an erratically moving robo-beetle, researchers found that the two main endocannabinoids in the brain have opposite effects on fear and panic responses.

Blocking the enzyme FAAH (which breaks down anandamide) with the drug URB597 reduced flight behavior and increased tolerance to the approaching beetle. This anti-panic effect was confirmed to work through CB1 receptors, as blocking those receptors eliminated the benefit.

In contrast, blocking MAGL (which breaks down 2-AG) with JZL184 actually increased flight behavior. This was unexpected given that both chemicals act through the same receptor system.

High-anxiety mice strains (HAB and BALB/c) showed decreased tolerance and increased avoidance of the beetle compared to normal-anxiety mice, validating the task as a measure of innate fear responses.

Why it matters

This study reveals that the two main endocannabinoids have distinct and even opposing roles in panic-like responses. Understanding this distinction is critical for developing cannabinoid-based treatments for anxiety and panic disorders, as targeting anandamide specifically may be more therapeutic than broadly activating the endocannabinoid system.

The numbers in context

URB597 at 0.3 mg/kg reduced flight behavior. JZL184 at 8 mg/kg increased flight behavior. Diazepam at 1 mg/kg increased tolerance but did not affect avoidance. CB1 antagonist SR141716A at 3 mg/kg blocked URB597 effects.

How the study worked

Researchers developed the "beetle mania task" (BMT) to study innate fear responses in mice confronted with an erratically moving robo-beetle. They tested multiple mouse strains with varying anxiety levels and administered pharmacological agents targeting the endocannabinoid system (URB597 for FAAH inhibition, JZL184 for MAGL inhibition, diazepam for comparison).

What this study cannot tell us

Animal study results may not translate directly to humans. The robo-beetle task is novel and has not been extensively validated across laboratories. Pharmacological doses may not reflect natural variation in endocannabinoid tone.

How to read the evidence

Animal study with controlled pharmacological manipulation. Preliminary evidence with clear mechanistic insights but not yet tested in humans.

When this study was published

Published in 2017.

The bigger picture

This finding helps explain why cannabis (which activates the whole endocannabinoid system) can paradoxically increase anxiety in some situations. The selective enhancement of anandamide, rather than broad cannabinoid activation, may be the key to unlocking anti-anxiety benefits without the risk of increased panic.

Questions still open

Could FAAH inhibitors serve as anti-panic medications in humans? Why do anandamide and 2-AG have opposite effects on fear despite acting on the same receptor? Would these findings hold in chronic treatment rather than single doses?

Common questions

What is anandamide?

Anandamide is one of two main endocannabinoids, chemicals your brain naturally produces that act on the same receptors as THC. This study found that selectively boosting anandamide reduced fear and panic responses in mice.

Why can cannabis both help and worsen anxiety?

This study suggests the answer may lie in the two different endocannabinoids. Anandamide appears to reduce panic while 2-AG may increase it. Cannabis activates both pathways, which could explain why its effects on anxiety are unpredictable.

Read the original research

Enhanced anandamide signaling reduces flight behavior elicited by an approaching robo-beetle.

Neuropharmacology, 126, 233-241

View on PubMed ↗Publisher’s paper ↗

Citation

Heinz, Daniel E; Genewsky, Andreas; Wotjak, Carsten T. (2017). Enhanced anandamide signaling reduces flight behavior elicited by an approaching robo-beetle.. Neuropharmacology, 126, 233-241. https://doi.org/10.1016/j.neuropharm.2017.09.010