title: Delta9-tetrahydrocannabinol decreases somatic and motivational manifestations of nicotine withdrawal in mice.
abstract: The possible interactions between Delta9-tetrahydrocannabinol (Delta9-THC) and nicotine remain unclear in spite of the current association of cannabis and tobacco in humans. The aim of the present study was to explore the interactions between these two drugs of abuse by evaluating the consequences of Delta9-THC administration on the somatic manifestations and the aversive motivational state associated with nicotine withdrawal in mice. Acute Delta9-THC administration significantly decreased the incidence of several nicotine withdrawal signs precipitated by mecamylamine or naloxone, such as wet-dog-shakes, paw tremor and scratches. In both experimental conditions, the global withdrawal score was also significantly attenuated by acute Delta9-THC administration. This effect of Delta9-THC was not due to possible adaptive changes induced by chronic nicotine on CB1 cannabinoid receptors, as the density and functional activity of these receptors were not modified by chronic nicotine administration in the different brain structures investigated. We also evaluated the consequences of Delta9-THC administration on c-Fos expression in several brain structures after chronic nicotine administration and withdrawal. c-Fos was decreased in the caudate putamen and the dentate gyrus after mecamylamine precipitated nicotine withdrawal. However, acute Delta9-THC administration did not modify c-Fos expression under these experimental conditions. Finally, Delta9-THC also reversed conditioned place aversion associated to naloxone precipitated nicotine withdrawal. Taken together, these results indicate that Delta9-THC administration attenuated somatic signs of nicotine withdrawal and this effect was not associated with compensatory changes on CB1 cannabinoid receptors during chronic nicotine administration. In addition, Delta9-THC also ameliorated the aversive motivational consequences of nicotine withdrawal.
authors.affiliation: Laboratori de Neurofarmacologia. Facultat de Ciències de la Salut i de la Vida. Universitat Pompeu Fabra. C/Dr Aiguader, 80. 08003 Barcelona, Spain.
authors.forename: Graciela N
authors.initials: GN
authors.lastname: Balerio
authors.forename: Ester
authors.initials: E
authors.lastname: Aso
authors.forename: Fernando
authors.initials: F
authors.lastname: Berrendero
authors.forename: Patricia
authors.initials: P
authors.lastname: Murtra
authors.forename: Rafael
authors.initials: R
authors.lastname: Maldonado
mesh_terms: D018712:Analgesics, Non-Narcotic / Q000627:therapeutic use; D000704:Analysis of Variance; D000818:Animals; D001345:Autoradiography / Q000379:methods; D001522:Behavior, Animal; D048588:Benzoxazines; D001921:Brain / Q000187:drug effects / Q000502:physiology; D002121:Calcium Channel Blockers / Q000493:pharmacokinetics; D002452:Cell Count / Q000379:methods; D003216:Conditioning, Operant / Q000187:drug effects; D013759:Dronabinol / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004347:Drug Interactions / Q000502:physiology; D007150:Immunohistochemistry / Q000379:methods; D066298:In Vitro Techniques; D008297:Male; D008464:Mecamylamine / Q000627:therapeutic use; D051379:Mice; D009025:Morpholines / Q000493:pharmacokinetics; D009042:Motivation; D009270:Naloxone / Q000627:therapeutic use; D009281:Naphthalenes / Q000493:pharmacokinetics; D009292:Narcotic Antagonists / Q000627:therapeutic use; D009538:Nicotine / Q000009:adverse effects*; D018722:Nicotinic Agonists / Q000009:adverse effects*; D018733:Nicotinic Antagonists / Q000627:therapeutic use; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D011869:Radioligand Assay / Q000379:methods; D013375:Substance Withdrawal Syndrome / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*
chemical_list: D018712:Analgesics, Non-Narcotic; D048588:Benzoxazines; D002121:Calcium Channel Blockers; D009025:Morpholines; D009281:Naphthalenes; D009292:Narcotic Antagonists; D018722:Nicotinic Agonists; D018733:Nicotinic Antagonists; D016760:Proto-Oncogene Proteins c-fos; D009270:Naloxone; C070417:(3R)-((2,3-dihydro-5-methyl-3-((4-morpholinyl)methyl)pyrrolo-(1,2,3-de)-1,4-benzoxazin-6-yl)(1-naphthalenyl))methanone; D008464:Mecamylamine; D009538:Nicotine; D013759:Dronabinol