» Articles » PMID: 15705714

CB2 Cannabinoid Receptor Activation Produces Antinociception by Stimulating Peripheral Release of Endogenous Opioids

Overview
Specialty Science
Date 2005 Feb 12
PMID 15705714
Citations 188
Authors
Affiliations
Soon will be listed here.
Abstract

CB(2) cannabinoid receptor-selective agonists are promising candidates for the treatment of pain. CB(2) receptor activation inhibits acute, inflammatory, and neuropathic pain responses but does not cause central nervous system (CNS) effects, consistent with the lack of CB(2) receptors in the normal CNS. To date, there has been virtually no information regarding the mechanism of CB(2) receptor-mediated inhibition of pain responses. Here, we test the hypothesis that CB(2) receptor activation stimulates release from keratinocytes of the endogenous opioid beta-endorphin, which then acts at opioid receptors on primary afferent neurons to inhibit nociception. The antinociceptive effects of the CB(2) receptor-selective agonist AM1241 were prevented in rats when naloxone or antiserum to beta-endorphin was injected in the hindpaw where the noxious thermal stimulus was applied, suggesting that beta-endorphin is necessary for CB(2) receptor-mediated antinociception. Further, AM1241 did not inhibit nociception in mu-opioid receptor-deficient mice. Hindpaw injection of beta-endorphin was sufficient to produce antinociception. AM1241 stimulated beta-endorphin release from rat skin tissue and from cultured human keratinocytes. This stimulation was prevented by AM630, a CB(2) cannabinoid receptor-selective antagonist and was not observed in skin from CB(2) cannabinoid receptor-deficient mice. These data suggest that CB(2) receptor activation stimulates release from keratinocytes of beta-endorphin, which acts at local neuronal mu-opioid receptors to inhibit nociception. Supporting this possibility, CB(2) immunolabeling was detected on beta-endorphin-containing keratinocytes in stratum granulosum throughout the epidermis of the hindpaw. This mechanism allows for the local release of beta-endorphin, where CB(2) receptors are present, leading to anatomical specificity of opioid effects.

Citing Articles

UK medical cannabis registry: A clinical outcome analysis of medical cannabis therapy in chronic pain patients with and without co-morbid sleep impairment.

Datta I, Erridge S, Holvey C, Coomber R, Guru R, Holden W Pain Pract. 2024; 25(1):e13438.

PMID: 39545361 PMC: 11683519. DOI: 10.1111/papr.13438.


Cannabinoid Analgesia in Postoperative Pain Management: From Molecular Mechanisms to Clinical Reality.

Carrascosa A, Navarrete F, Saldana R, Garcia-Gutierrez M, Montalban B, Navarro D Int J Mol Sci. 2024; 25(11).

PMID: 38892456 PMC: 11172912. DOI: 10.3390/ijms25116268.


Amyotrophic Lateral Sclerosis and Pain: A Narrative Review from Pain Assessment to Therapy.

Pota V, Sansone P, De Sarno S, Aurilio C, Coppolino F, Barbarisi M Behav Neurol. 2024; 2024:1228194.

PMID: 38524401 PMC: 10960655. DOI: 10.1155/2024/1228194.


Cutaneous targets for topical pain medications in patients with neuropathic pain: individual differential expression of biomarkers supports the need for personalized medicine.

Albrecht P, Liu Y, Houk G, Ruggiero B, Banov D, Dockum M Pain Rep. 2024; 9(2):e1119.

PMID: 38375092 PMC: 10876238. DOI: 10.1097/PR9.0000000000001121.


β-endorphin suppresses ultraviolet B irradiation-induced epidermal barrier damage by regulating inflammation-dependent mTORC1 signaling.

Kim H, Kim H, Hong Y, Son E, Cho S Sci Rep. 2023; 13(1):22357.

PMID: 38102220 PMC: 10724221. DOI: 10.1038/s41598-023-49886-5.


References
1.
Ho B, Uezono Y, Takada S, Takase I, Izumi F . Coupling of the expressed cannabinoid CB1 and CB2 receptors to phospholipase C and G protein-coupled inwardly rectifying K+ channels. Recept Channels. 1999; 6(5):363-74. View

2.
Shefler I, Seger R, Sagi-Eisenberg R . Gi-mediated activation of mitogen-activated protein kinase (MAPK) pathway by receptor mimetic basic secretagogues of connective tissue-type mast cells: bifurcation of arachidonic acid-induced release upstream of MAPK. J Pharmacol Exp Ther. 1999; 289(3):1654-61. View

3.
Buckley N, McCOY K, Mezey E, Bonner T, Felder C, Glass M . Immunomodulation by cannabinoids is absent in mice deficient for the cannabinoid CB(2) receptor. Eur J Pharmacol. 2000; 396(2-3):141-9. DOI: 10.1016/s0014-2999(00)00211-9. View

4.
Rittner H, Brack A, Machelska H, Mousa S, Bauer M, Schafer M . Opioid peptide-expressing leukocytes: identification, recruitment, and simultaneously increasing inhibition of inflammatory pain. Anesthesiology. 2001; 95(2):500-8. DOI: 10.1097/00000542-200108000-00036. View

5.
Malan Jr P, Ibrahim M, Deng H, Liu Q, Mata H, Vanderah T . CB2 cannabinoid receptor-mediated peripheral antinociception. Pain. 2001; 93(3):239-245. DOI: 10.1016/S0304-3959(01)00321-9. View