Introduction: The protective and antisecretory effects of dopamine agonists on the stomach have been already reported, but the effect of bromocriptine (D2 dopamine agonist) on histamine stimulated gastric acid secretion (GAS) needs to be investigated. Methods: For gastric sampling, animals were anesthetized and a polyethylen tube was introduced into the stomach through esophagus. A cannula ...

The effects of antipsychotic drugs have generally been considered to be mediated by blockade of dopamine D2 receptors. The concept of limbic and cortical selectivity of second-generation antipsychotics, i.e. higher dopamine D2 receptor occupancy in the cerebral cortices than in the striatum, has been suggested to explain their clinical efficacy with lower incidence of extrapyramidal side-effect...

Dopamine D1 and D2 receptors may synergize with or oppose each other's effects. We suggest that stimulation of D1 and D2 receptors in the medial preoptic area (MPOA) of male rats have opposing effects on genital reflexes. In Experiment 1 a D1 agonist injected into the MPOA increased the number of ex copula erections but decreased the number of seminal emissions. In Experiment 2 a D1 antagonist ...

Although antipsychotics have been available for almost 70 years and greatly improved outcomes individuals with schizophrenia, all currently options derive their efficacy from blockade of dopaminergic receptors. However, this mechanism action leaves many symptoms unresolved is associated a significant side effect burden. The mechanisms underlying which were initially thought to be related excess...

Five or more dopamine receptor genes are expressed in brain. However, the pharmacological similarities of the encoded D1-D5 receptors have hindered studies of the localization and functions of the subtypes. To better understand the roles of the individual receptors, antibodies were raised against recombinant D1 and D2 proteins and were shown to bind to the receptor subtypes specifically in West...

Dopamine receptor subtypes have been classified generally as D1-like (e.g., D1, D5) or D2-like (D2, D3, D4), and converging evidence suggests that D2-like receptors may be especially important in mediating the abuse-related effects of cocaine. However, it has been difficult to differentiate the roles of the D2-like receptor subtypes in the behavioral effects of cocaine because of the relatively...

Agonist stimulated [S]guanosine 5¢-c-thiotriphosphate ([S]GTPcS) binding autoradiography was established for the examination of dopamine-D2 ⁄D3 receptors in human brain sections. The distribution of G proteins activated by dopamine-D2 ⁄D3 receptors was studied in whole hemisphere cryosections. Dopamine stimulated [S]GTPcS binding in brain regions with high densities of dopamine D2-like receptor...

This study was designed to validate an in vivo measurement of the functional sensitivity of basal ganglia neuronal circuits containing dopamine D2 receptors. We hypothesized that a D2 agonist would decrease striatopallidal neuronal activity, and hence regional cerebral blood flow (rCBF) over the axon terminals in the globus pallidus. Quantitative pallidal blood flow was measured using positron ...

OBJECTIVE Dopamine exists in the immune system and has obvious immunomodulating action. However, receptor mechanism underlying the dopamine immunomodulation remains to be clarified. In the present study, we provide the evidence for existence of dopamine receptor subtypes in T lymphocytes and show the roles of the receptors and the receptor-coupled signaling in mediating the dopamine immunomodul...

Anti-psychotic drugs The anti-psychotic drugs, e.g. haloperidol and chlorpromazine, comprise a large group of drugs that are used to treat the symptoms of schizophrenia [ l ] . The principal therapeutic effect of the drugs is on the positive (psychotic) symptoms of the disorder, although some drugs, e.g. clozapine, are claimed to have effects on the negative symptoms. After the discovery of dop...