Synthetic cannabinoid JWH-073 causes greater blood vessel relaxation than THC in mice | Research

The takeaway

Neither THC nor the synthetic cannabinoid JWH-073 killed cardiac cells at the doses tested, but JWH-073 produced significantly greater blood vessel relaxation, suggesting higher vascular risk.

People interested in the cardiovascular risks of synthetic cannabinoids versus natural cannabis.

96% maximal arterial relaxation with JWH-073

What the researchers found

JWH-073 produced significantly greater maximal relaxation of mesenteric arteries (96% vs. lower for THC) and greater maximal contractile response compared to THC. Neither compound caused cardiac myocyte death in vivo or in cultured heart cells at the concentrations studied.

Why it matters

K2/Spice products containing synthetic cannabinoids like JWH-073 have been linked to serious cardiovascular events. This study provides a mechanistic explanation: synthetic cannabinoids may cause more extreme blood vessel dilation than plant-derived THC.

The numbers in context

JWH-073 maximal arterial relaxation: 96% +/- 2%. No cardiac myocyte death observed with either compound. Both compounds produced typical cannabinoid effects (antinociception and hypothermia).

How the study worked

Male C57BL/6 mice received JWH-073 or THC, with cardiac injury assessed by histology. Additional experiments measured H9C2 cardiac cell viability after 24-hour treatment and ex vivo mesenteric artery vascular reactivity from drug-naive animals.

What this study cannot tell us

Used male mice only, so sex-specific effects are unknown. The doses and concentrations may not reflect typical human recreational exposure. In vitro vascular reactivity does not capture the full complexity of cardiovascular regulation in a living body.

How to read the evidence

Preliminary animal study using male mice only. While it identifies a plausible mechanism for synthetic cannabinoid cardiovascular risk, translation to human physiology requires further research.

When this study was published

Published in 2024 with data from controlled laboratory experiments.

The bigger picture

Reports of heart attacks, strokes, and blood pressure drops in K2/Spice users have raised alarms, but the biological mechanism has been unclear. This study points to enhanced vascular reactivity as a potential explanation for why synthetic cannabinoids are more cardiovascularly dangerous than THC.

Questions still open

Do other synthetic cannabinoids found in K2/Spice products show similar enhanced vascular effects? Would chronic exposure produce different results than acute dosing? Are there dose thresholds where THC also becomes cardiovascularly dangerous?

Common questions

What is JWH-073?

JWH-073 is a synthetic cannabinoid commonly found in K2/Spice herbal blends sold as recreational products. It activates the same CB1 receptors as THC but with different potency and pharmacological properties.

Does THC cause heart damage?

In this study, neither THC nor JWH-073 caused cardiac cell death at the doses tested. However, JWH-073 produced significantly more blood vessel dilation, which could contribute to cardiovascular events like blood pressure drops.

Read the original research

Effects of Δ9-Tetrahydrocannabinol and the Aminoalkylindole K2/Spice Constituent JWH-073 on Cardiac Tissue and Mesenteric Vascular Reactivity.

Cannabis and cannabinoid research, 9(4), e1056-e1062

View on PubMed ↗Publisher’s paper ↗

Citation

Breivogel, Chris S; Brenseke, Bonnie M; Eldeeb, Khalil; Nichols, Katlyn; Jonas, Amreen; Mistry, Artik H; Barbalato, Laura; Luibil, Nicholas; Howlett, Allyn C; Leone-Kabler, Sandra; Hilgers, Rob P H; Pulgar, Victor M. (2024). Effects of Δ9-Tetrahydrocannabinol and the Aminoalkylindole K2/Spice Constituent JWH-073 on Cardiac Tissue and Mesenteric Vascular Reactivity.. Cannabis and cannabinoid research, 9(4), e1056-e1062. https://doi.org/10.1089/can.2022.0325