title: Sex-related effects of agmatine on caffeine-induced locomotor activity in Swiss Webster mice.
abstract: In mammalian brain, agmatine is an endogenous amine that is synthesized through the decarboxylation of l-arginine by arginine decarboxylase. It has been proposed as a new neurotransmitter and/or neuromodulator. It was shown that agmatine had some beneficial effects in animal models of opioid and alcohol addiction. Locomotor stimulant properties of drugs such as ethanol, caffeine, nicotine and amphetamine have been linked to their addictive properties. The present study investigates the effects of agmatine on caffeine-induced locomotor activity both in male and female mice. Adult Swiss Webster mice were used in the study. Locomotor activity was measured for 30min immediately following caffeine (2.5, 5, 10 and 20mg/kg, i.p.) or saline treatments. Agmatine (5, 10 and 20mg/kg, i.p.) were injected 20min before caffeine (2.5 and 5mg/kg, i.p.) administration. In both sexes, agmatine (5-20mg/kg) were also tested for ability to depress or stimulate locomotor activity in the absence of caffeine. Caffeine (5mg/kg) induced a significant increase in locomotor activity of both male and female mice. There was no significant difference in the locomotor-activating effects of caffeine between male and female mice. Agmatine blocked the caffeine (5mg/kg)-induced locomotor stimulation dose dependently in male but not female mice. Agmatine had not any effect on the lower dose (2.5mg/kg) of caffeine in both sexes. These results suggest that agmatine has sex-related inhibitory effects on caffeine-induced locomotor activity in Swiss Webster mice, and male mice are more sensitive than the females to the effect of agmatine.
authors.affiliation: Gulhane Military Medical Academy, Department of Medical Pharmacology, Psychopharmacology Research Unit, Ankara, Turkey. tuzbay@gata.edu.tr <tuzbay@gata.edu.tr>
authors.forename: Tayfun
authors.initials: T
authors.lastname: Uzbay
authors.forename: Akin
authors.initials: A
authors.lastname: Kose
authors.forename: Hakan
authors.initials: H
authors.lastname: Kayir
authors.forename: Gokhan
authors.initials: G
authors.lastname: Ulusoy
authors.forename: Turgay
authors.initials: T
authors.lastname: Celik
mesh_terms: D000376:Agmatine / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005260:Female; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects*; D011897:Random Allocation; D012737:Sex Factors
chemical_list: D004338:Drug Combinations; D002110:Caffeine; D000376:Agmatine