Using the BOLD MR signal to differentiate the stereoisomers of ketamine in the rat.

Rationale: Ketamine is a chiral molecule that is reported to model aspects of schizophrenia.

Objectives: To investigate the stereospecificity of the isomers of ketamine using pharmacological magnetic resonance imaging (phMRI) in order to further understand ketamine's pharmacodynamic actions.

Method: Responses to 25 mg kg-1S(+) isomer, R(-) isomer and racemic ketamine in independent groups of Sprague-Dawley rats were investigated using a prepulse inhibition paradigm, locomotor observations, MRI and 2-deoxyglucose techniques.

Mapping the central effects of ketamine in the rat using pharmacological MRI.

Rationale: Ketamine induces, in both humans and rodents, behaviours analogous to some of the symptoms of schizophrenia.

Objectives: To utilise pharmacological magnetic resonance imaging (phMRI) techniques that identify changes in blood-oxygenation-level-dependent (BOLD) contrast to determine the temporal and spatial neuronal activation profile of ketamine in the rat brain.

Method: To obtain a pharmacodynamic profile of the drug, we assessed changes in locomotor activity after vehicle and 10 and 25 mg/kg ketamine.