Abstract
Agmatine is an endogenous polyamine, identified in mammalian brain, which meets the main criteria to be considered a neurotransmitter. Agmatine-like immunoreactivity has been described in numerous brain regions which have long been implicated in the regulation of anxiety. However, animal preclinical studies investigating effects of agmatine on anxiety are unclear. In this study, an attempt was made to clarify the actions of agmatine (7.5-60 mg/kg, ip) on anxiety tested in the elevated plus maze mice. Moreover, the possible development of tolerance to the effects of agmatine on anxiety after its subchronic administration for 7 consecutive days was also examined. A number of classical parameters were collected (open arm duration and frequency, closed arm duration and frequency and central platform duration and frequency). Different ethological measures were also obtained (rearings, headdipping and stretched attend posture). Results showed that agmatine did not produce any significant behavioural change in any of the parameters examined, suggesting that it might not be involved in the regulation of anxiety in mice.
