Psychopharmacology
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Randomized Controlled Trial Clinical Trial
Subjective, psychomotor, and physiological effects of cumulative doses of mixed-action opioids in healthy volunteers.
Conducting complete dose-response evaluations of multiple drugs in a single within-subjects experiment is very time-consuming when a complete session is required for evaluation of each dose. ⋯ Orderly dose-response functions and replication of results of single-dosing studies confirmed that the cumulative-dosing procedure is an efficient way of determining dose-response functions for multiple opioids within the same subjects.
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Multiple low doses of cocaine (COC) may cause intermittent vasoconstriction and reperfusion, leading to elevations in damaging reactive oxygen species, such as hydroxyl free radicals (*OH). Salicylate may offer protection because it reacts with *OH and/or because of its anti-inflammatory actions. ⋯ Our unexpected findings may be of clinical relevance because of the use of aspirin for treatment of misdiagnosed "preeclamptic" COC-abusing pregnant women and its possible use for COC abusers at risk for reduced cerebral blood flow and stroke.
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Randomized Controlled Trial Multicenter Study Clinical Trial
Intramuscular (IM) ziprasidone 20 mg is effective in reducing acute agitation associated with psychosis: a double-blind, randomized trial.
Intramuscular (IM) conventional antipsychotics and/or benzodiazepines are effective in the short-term treatment of acutely agitated psychotic patients but may be associated with adverse effects. A short-acting IM formulation of the novel antipsychotic, ziprasidone, which may offer advantages over conventional agents, has been developed. ⋯ Ziprasidone IM 20 mg substantially and significantly reduced the symptoms of acute agitation in patients with psychotic disorders. Ziprasidone 20 mg IM was very well tolerated and produced no dystonia or akathisia.
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Although the rewarding effects of cocaine are generally attributed to its ability to increase dopamine (DA) transmission, cocaine demonstrates approximately equal affinity for dopamine and serotonin (5-HT) transporters in vitro. However, there have been few direct systematic comparisons of the effects of cocaine on DA and 5-HT transmission in vivo. ⋯ Cocaine produced a larger impact on DA than 5-HT neurotransmission under specific conditions. A series of physiological mechanisms, i.e. terminal density, neurotransmitter interactions and somatodendritic regulation, are discussed as factors responsible for facilitating cocaine's effects on DA relative to 5-HT.
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Electrical stimulation of the dorsal periaqueductal gray matter (dPAG) and the inferior colliculus (IC) has been used as an aversive unconditioned stimulus. However, studies on the behavioral, sensorial and autonomic components of the conditioned fear elaborated in the midbrain tectum are lacking. ⋯ 1) Conditioned freezing may be produced using the electrical stimulation of the dPAG or IC as unconditioned stimuli, 2) only the pairing of CS plus dPAG but not with IC stimulation, produces significant conditioned antinociception, 3) blockade of 5-HT2A receptors inhibits conditioned antinociception but not the conditioned defensive behavior using the electrical stimulation of the dPAG as unconditioned stimulus.