Nitric oxide (NO) and central dopamine (DA) D3 receptor reactivity to quinpirole in rats.

Nitric oxide (NO) has been implicated in large number of pathologies and in normal physiological function of the brain. The aim of this study was to recognize the effect of Nitro-L-Arginine Methyl Ester.HCl (NAME) and L-Arginine Ethyl Ester.HCl (ARGININE) on reactivity of the central DA D3 receptor to agonist (Quinpirole) in rats. For this reason we have been used specific behavioural procedure such yawning behaviour which is mediated via central DA D3 receptors. Experiments were perform in adult male Wistar rats treated daily with quinpirole (0.05 mg/kg IP) or vehicle (0.9% NaCl) for the first 11 days from birth to obtain of the central D3 receptor supersensitivity. NAME and ARGININE in different way modified response of the central DA receptor to quinpirole estimated by means yawning behavioural procedure.