Involvement of nitric oxide system in enhancement of morphine-induced conditioned place preference by agmatine in male mice.
Agmatine recently has been suggested as a neurotransmitter, is able to interact with various effects of morphine like analgesia and dependence. In this study, the effects of agmatine on rewarding properties of morphine, and the possible involvement of nitric oxide (NO) system has been evaluated in an unbiased conditioned place preference (CPP) paradigm. Agmatine (1, 5 and 10mg/kg, i.p.) alone induced neither CPP nor conditioned place aversion (CPA). Morphine (0.01, 0.05, 0.1 and 0.5mg/kg, s.c.), while unable to show CPP or CPA, induced CPP in mice pretreated with agmatine. L-arginine (200mg/kg, i.p.), a NO precursor, significantly enhanced the effect of agmatine (5mg/kg) on morphine (0.5mg/kg)-induced place preference. NG-nitro-L-arginine methyl ester (L-NAME; 2.5mg/kg, i.p.), a non specific nitric oxide synthase (NOS) inhibitor, and aminoguanidine (50 and 100mg/kg, i.p.), a specific inducible NOS inhibitor, significantly reduced the effect of agmatine (5mg/kg) on morphine (0.5mg/kg)-induced place preference. These results suggest the possible involvement of inducible nitric oxide system in potentiating effects of agmatine on morphine-induced place preference.
Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Mohammad Ali
MA
Khoshnoodi
Rouzbeh
R
Motiei-Langroudi
Pouya
P
Tahsili-Fahadan
Noushin
N
Yahyavi-Firouz-Abadi
Mohammad Hossein
MH
Ghahremani
Ahmad Reza
AR
Dehpour
D000376:Agmatine / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D003216:Conditioning, Operant / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D051379:Mice; D009020:Morphine / Q000494:pharmacology*; D009294:Narcotics / Q000494:pharmacology*; D009569:Nitric Oxide / Q000502:physiology*
D004791:Enzyme Inhibitors; D009294:Narcotics; D009569:Nitric Oxide; D000376:Agmatine; D009020:Morphine