title: Combined administration of buprenorphine and naltrexone produces antidepressant-like effects in mice.
abstract: Opiates have been used historically for the treatment of depression. Renewed interest in the use of opiates as antidepressants has focused on the development of kappa opioid receptor (κ-receptor) antagonists. Buprenorphine acts as a partial µ-opioid receptor agonist and a κ-receptor antagonist. By combining buprenorphine with the opioid antagonist naltrexone, the activation of µ-opioid receptors will be reduced and the κ-antagonist properties enhanced. We have established that a combination dose of buprenorphine (1 mg/kg) with naltrexone (1 mg/kg) functions as a short-acting κ-antagonist in the mouse tail withdrawal test. Furthermore, this dose combination is neither rewarding nor aversive in the conditioned place preference paradigm, and is without significant locomotor effects. We have shown for the first time that systemic co-administration of buprenorphine (1 mg/kg) with naltrexone (1 mg/kg) in CD-1 mice produced an antidepressant-like response in behaviours in both the forced swim test and novelty induced hypophagia task. Behaviours in the elevated plus maze and light dark box were not significantly altered by treatment with buprenorphine alone, or in combination with naltrexone. We propose that the combination of buprenorphine with naltrexone represents a novel, and potentially a readily translatable approach, to the treatment of depression.
authors.affiliation: Department of Pharmacy and Pharmacology, University of Bath, Bath, UK.
authors.forename: Abdulrahman
authors.initials: A
authors.lastname: Almatroudi
authors.affiliation: Department of Pharmacy and Pharmacology, University of Bath, Bath, UK.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Husbands
authors.affiliation: Department of Pharmacy and Pharmacology, University of Bath, Bath, UK.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Bailey
authors.affiliation: Department of Pharmacy and Pharmacology, University of Bath, Bath, UK S.Bailey@bath.ac.uk.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Bailey
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D000928:Antidepressive Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002047:Buprenorphine / Q000008:administration & dosage / Q000494:pharmacology*; D003863:Depression / Q000188:drug therapy*; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D051379:Mice; D009271:Naltrexone / Q000008:administration & dosage / Q000494:pharmacology*; D009292:Narcotic Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D017473:Receptors, Opioid, kappa / Q000037:antagonists & inhibitors; D017450:Receptors, Opioid, mu / Q000187:drug effects / Q000378:metabolism
chemical_list: D000701:Analgesics, Opioid; D000928:Antidepressive Agents; D009292:Narcotic Antagonists; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; D002047:Buprenorphine; D009271:Naltrexone
keywords: Depression; anxiety; kappa antagonist; kappa opioid receptor; mu agonist