Cannabinoid Receptors, Mental Pain and Suicidal Behavior: a Systematic Review
Purpose of Review
The current serotonin-based biological model of suicidal behavior (SB) may be too simplistic. There is emerging evidence that other biomarkers and biological systems may be involved in SB pathophysiology. The literature on the endocannabinoid (EC) systems and SB is limited. The objective of the present article is to review all available information on the relationship between cannabinoid receptors (CB1 and CB2 receptors), and SB and/or psychological pain.
Our review is limited by the small number and heterogeneity of studies identified: (1) an autopsy study describing elevated levels of CB1 receptor activity in the prefrontal cortex and suicide in both depression and alcoholism and (2) studies supporting the involvement of both CB1 and CB2 receptors in the regulation of neuropathic pain and stress-induced analgesia.
We conclude that cannabinoid receptors, particularly CB1 receptors, may become promising targets for the development of novel therapeutic tools for the treatment of SB.
KeywordsCannabinoid receptors Suicidal behavior Mental pain Psychological pain
The authors acknowledge Lorraine Maw, M.A., at the Mental Health Research Center at Eastern State Hospital, Lexington, KY, who helped in editing this article. This article was written for publication without any external funding.
Compliance with Ethical Standards
Conflict of Interest
Laura Colino, Javier Herranz-Herrer, Elena Gil-Benito, Teresa Ponte-Lopez, Pablo del Sol-Calderon, Maria Rodrigo-Yanguas, María Gil-Ligero, Antonio J Sánchez-López, and Jose de Leon declare no conflict of interest.
In the last 24 months Hilario Blasco-Fontecilla received lecture fees from AB-Biotics, Praxis Pharmaceuticals, and Shire.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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