there is interrelationship between the immune and nervous systems that is accomplished by the molecular mediators. dopamine is one of the most important neurotransmitters. five different dopamine receptor genes (drd1, drd2, drd3, drd4, and drd5) have been recognized and cloned. the expression of the dopamine receptors is well characterized in the brain but little work has been done to examine t...

A randomised, double blind, single dose study of topical haloperidol, a dopamine receptor blocking drug, was performed on 20 healthy volunteers. After its administration a modest reduction in intraocular pressure was recorded over the six-hour study period, but the difference was not significant at the p less than 0.05 level. Although dopamine blocking agents are effective in reducing intraocul...

In the present study, interactive effects of D1 and D2 dopamine receptors antagonists and different periods of lithium pretreatment on morphine dependence in mice have been investigated. This study was designed to investigate whether the hypothesis that lithium and dopaminergic mechanisms via their effects on phosphoinositide pathways and calcium flux could influence morphine withdrawal respons...

A major line of evidence that supports the hypothesis of dopamine overactivity in schizophrenia is the psychomimetic potential of agents such as amphetamine that stimulate dopamine outf low. A novel brain imaging method provides an indirect measure of in vivo synaptic dopamine concentration by quantifying the change in dopamine receptor radiotracer binding produced by agents that alter dopamine...

In the present study, the effects of different doses of nicotine on immobility time in mice were tested. Intraperitioneal administration of low doses of nicotine (0.025 mg/kg) decreased, but higher doses (0.8 and 1 mg/kg) increased immobility time. The anti-immobility response induced by low doses of nicotine was inhibited by high doses of the D2 receptor antagonist sulpiride, the central nicot...

Evidence from psychopharmacological research has revealed that dopamine receptor agents have opposite effects on cognitive function depending on baseline levels of working memory capacity. These contrasting effects have been interpreted to reflect differential baseline levels of dopamine. Here we demonstrate for the first time that working memory capacity as measured by listening span predicts ...

INTRODUCTION A large part of research into drug addiction focuses on mesolimbic dopamine circuitry; however, both alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and/or kainate and dopamine D2 receptors can play a role in maintaining the established addiction. CASE PRESENTATION We report the case of a 34-year-old man who compulsively smoked 80 to 100 cigarettes each day. After receiv...

Postsynaptic Neuron Figure 1. Conventional vs. Atypical Antipsychotic Mechanisms n last month’s BRAINSTORMS, we discussed a new hypothesis on the mechanism of action of atypical antipsychotics, namely the “hit-and-run” hypothesis. Here we illustrate this concept. Conventional: Because of the biochemical properties of conventional antipsychotics, their binding to postsynaptic dopamine D2 recepto...

If a physiological, biochemical or anatomical variable has a normal distribution then the tails of such a distribution may be associated with pathological function. In certain cases this can lead to a bimodal distribution for the variable in individuals with the resultant pathology. We illustrate with a study of dopamine receptors. PET data suggest that the distribution of dopamine DA2 receptor...