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Updated: Jul 16, 2026
07:48
Tracking Drug-induced Changes in Receptor Post-internalization Trafficking by Colocalizational Analysis
Published on: July 3, 2015
Molecular characterization of a peripheral receptor for cannabinoids
S Munro1, K L Thomas, M Abu-Shaar
1MRC Laboratory of Molecular Biology, Cambridge, UK.
Nature
|September 2, 1993
Summary
Researchers discovered a new cannabinoid receptor in spleen macrophages, distinct from the brain receptor. This finding may explain non-psychoactive effects of cannabinoids and offers new therapeutic targets.
Area of Science:
- Pharmacology
- Immunology
- Neuroscience
Background:
- Delta 9-tetrahydrocannabinol (delta 9-THC), a primary marijuana component, has historical psychoactive uses.
- Cannabinoids exhibit diverse effects, including pain relief, anti-inflammation, and anti-emesis, but clinical use is limited by psychoactivity.
- A previously identified cannabinoid receptor is primarily in the brain, suggesting other mechanisms for non-psychoactive effects.
Purpose of the Study:
- To identify novel cannabinoid receptors involved in the non-psychoactive effects of cannabinoids.
- To elucidate the biochemical basis of cannabinoid action beyond the known brain receptor.
Main Methods:
- Cloning of a gene encoding a novel G-protein-coupled receptor for cannabinoids.
- Analysis of receptor expression patterns in various tissues, focusing on immune cells.
Main Results:
- A novel cannabinoid receptor was cloned and found to be expressed in macrophages within the spleen's marginal zone.
- This receptor is notably absent in the brain, differentiating it from the previously known cannabinoid receptor.
- Low expression was observed in testes, but not in other peripheral tissues.
Conclusions:
- The newly identified spleen receptor may mediate some of the non-psychoactive, potentially anti-inflammatory or immunomodulatory, effects of cannabinoids.
- This discovery opens avenues for developing cannabinoid-based therapeutics with reduced psychoactive side effects.
- Further research is warranted to fully understand the role of this receptor in immune function and cannabinoid signaling.
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