morphine was used as a remedy for the control of diarrhea centuries before it's sedative-analgesic effect was discovered. although several mechanisms have been proposed for the morphine-induced inhibition of gastrointestinal transit (oit), the exact mechanism has not yet been identified. on this basis the possible involvement of the dopaminergic system in morphine-induced inhibition of tra...

The amygdala, a critical structure for both Pavlovian fear conditioning and fear extinction, receives sparse but comprehensive dopamine innervation and contains dopamine D1 and D2 receptors. Fear extinction, which involves learning to suppress the expression of a previously learned fear, appears to require the dopaminergic system. The specific roles of D2 receptors in mediating associative lear...

BACKGROUND In treatment-resistant schizophrenia a combination of ECT with antipsychotics has been reported to have superior outcomes compared to other strategies, however the results were inconsistent. We investigated the long-term effects of the combination of unilateral, non-dominant hemisphere ECT with three antipsychotics. SUBJECTS AND METHODS The clinical study was a naturalistic, prospe...

The amplitude and phase of the second harmonic (15 Hz) of the electroretinographic responses to three different spatial frequency grating stimuli (0.25, 1 and 4 c/deg), reversed at 7.5 Hz, were studied i normal human subjects, before and 30 min after the systemic administration of three doses (0.071, 0.357 or 1.428 mg/kg) of a selective D2 blocker, l-sulpiride, to three populations of 18, 19, o...

(+/-)Isofloxythepin (0.32-3.2 mg/kg, i.p.) significantly inhibited in a dose-dependent manner wet-dog shaking (WDS) induced by electrical stimulation of the rat hippocampus. In addition, both optical isomers of isofloxythepin inhibited WDS, with the (-)-isomer being almost 3 times more potent than the (+)-isomer. Other neuroleptics such as haloperidol, chlorpromazine, zotepine and sulpiride als...

Episodic memory, working memory, emotional memory, and attention are subject to dopaminergic modulation. However, the potential role of dopamine on the generation of false memories is unknown. This study defined the role of the dopamine D2 receptor on true and false recognition memories. Twenty-four young, healthy volunteers ingested a single dose of placebo or 400 mg oral sulpiride, a dopamine...

In this study, the influence of dopamine receptor agonists and antagonists on antinociception induced by bac10fen has been examined in the formalin test. The GABA-B agonist bac10fen induced antinociception in both phases of the formalin test in mice. The dopamine receptor agonists SKF 38393 and quinpirole also induced antinociception in both phases of the test. SKF 38393 but not quinpirole ...