Tehran University of Medical Sciences

Science Communicator Platform

Stay connected! Follow us on X network (Twitter):
Share this content! On (X network) By
Involvement of Opioid System in Antidepressant-Like Effect of the Cannabinoid Cb1 Receptor Inverse Agonist Am-251 After Physical Stress in Mice Publisher Pubmed



Ostadhadi S1, 2, 3 ; Hajmirzaian A1, 2 ; Nikoui V1, 2 ; Kordjazy N1, 2 ; Dehpour AR1, 2, 3
Authors
Show Affiliations
Authors Affiliations
  1. 1. Experimental Medicine Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
  2. 2. Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
  3. 3. Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran

Source: Clinical and Experimental Pharmacology and Physiology Published:2016


Abstract

Cannabinoid inverse agonists possess antidepressant-like properties, but the mechanism of this action is unknown. Numerous studies have reported the interaction between opioid and cannabinoid pathways. In this study, acute foot-shock stress was used in mice to investigate the involvement of the opioid pathway in the antidepressant-like effect of the cannabinoid CB1 receptor inverse agonist AM-251. Stress was induced by intermittent foot-shock stimulation for 30 min. Then, using the forced swimming test (FST) and tail suspension test (TST), the immobility time was measured. Results show that the immobility time was significantly prolonged in animals subjected to foot-shock stress, compared with non-stressed controls (P < 0.01). Also, the serum corticosterone level was significantly increased after stress induction (P < 0.001). Administration of AM-251 (0.5 and 0.3 mg/kg, intraperitoneally (i.p.)), significantly decreased the immobility time of stressed mice in the FST (P < 0.001 and P < 0.01, respectively) and TST (P < 0.01 and P < 0.05, respectively). The lowest dose of AM-251 (0.1 mg/kg), naltrexone (0.3 mg/kg), and morphine (1.0 mg/kg) did not show any significant effect on stressed animals (P > 0.05). Co-administration of AM-251 with sub-effective dose of naltrexone decreased the effective dose of this cannabinoid inverse agonist, to 0.1 mg/kg (P < 0.01). On the other hand, administration of the sub-effective dose of morphine reversed the anti-immobility effect of AM-251 (0.5 mg/kg; P < 0.001). In conclusion, the present study for the first time reveals the possible role of opioid signalling in the antidepressant-like properties of AM-251 in a foot-shock stress model. © 2016 John Wiley & Sons Australia, Ltd.
Experts (# of related papers)
Other Related Docs