It is obvious that DA is an important neurotransmitter in vivo. It is involved in a variety of physiological processes such as mental processes, motor function and hormone regulation. In this context, it is quite understandable that a DA D2 receptor antagonist that inhibits the DA D2 receptor regardless of the state of activity of dopaminergic neurotransmission and inhibit the physiological fun...

Dopamine-dependent compensation maintains motor behavior in mice with developmental ablation of dopaminergic neurons.

The aim of this chapter is to bring together data from anatomical, neurochemical, physiological, and behavioral studies in an attempt to understand how the properties of the microcircuits of the striatum can underlie behavior in reward-related paradigms. The canonical microcircuit of the striatum in relation to corticostriatal and dopaminergic afferents is first described. Mechanisms of the sel...

Several behaviours associated with anorexia nervosa (AN) are hypothesised to be highly salient and rewarding for these people (e.g., food restriction, weight-loss, and driven exercise). Neurobiological and psychophysiological evidence support a role for altered dopaminergic reward processes in the aetiology of AN and in the valued nature of its symptomatology. More specifically, preliminary dat...

Bromocriptine, a dopamine agonist, alleviates symptoms of Parkinson's disease, even when administered alone, and is used for its treatment. Better therapeutic effects are, however, achieved when bromocriptine is used in combination with levodopa. In this study, we examined the biochemical changes caused by bromocriptine administration with and without levodopa, and evaluated the effects of the ...

Dopamine (DA) regulates emotional and motivational behavior through the mesolimbic dopaminergic pathway. Changes in DA signaling in mesolimbic neurotransmission are widely believed to modify reward-related behaviors and are therefore closely associated with drug addiction. Recent evidence now suggests that as with drug addiction, obesity with compulsive eating behaviors involves reward circuitr...

We hypothesize that drug addiction can be viewed as the endpoint of a series of transitions from initial voluntary drug use through the loss of control over this behaviour, such that it becomes habitual and ultimately compulsive. We describe evidence that the switch from controlled to compulsive drug seeking represents a transition at the neural level from prefrontal cortical to striatal contro...

Updating of working memory has been associated with striato-frontal brain regions and phasic dopaminergic neurotransmission. We assessed raclopride binding to striatal dopamine (DA) D2 receptors during a letter-updating task and a control condition before and after 5 weeks of updating training. Results showed that updating affected DA activity before training and that training further increased...

The mesolimbic dopaminergic reward system is responsible for the negative affective symptomatology of schizophrenia, which may be related to a low dopamine tonus within the ventral striatum. The monetary incentive delay (MID) task can be used to study the response of the ventral striatum to incentive stimuli. We show that activation of the ventral striatum is low in patients with schizophrenia,...

In man, non emetic doses of apomorphine elicit a series of behavioural, neurological and psychological changes which are difficult to ascribe to the stimulation of postsynaptic dopamine receptors. Since similar effects are elicited by neuroleptic drugs, the functional changes induced by apomorphine in man might be interpreted as being the result of a decreased dopaminergic activity. The sedatio...