Psychopharmacology
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Randomized Controlled Trial
Effect of a novel histamine subtype-3 receptor inverse agonist and modafinil on EEG power spectra during sleep deprivation and recovery sleep in male volunteers.
Histamine and dopamine contribute to the maintenance of wakefulness. ⋯ Both MK-0249 and modafinil exert effects on the EEG which are consistent with wake promotion.
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Randomized Controlled Trial Comparative Study
Interaction between expectancies and drug effects: an experimental investigation of placebo analgesia with caffeine as an active placebo.
In a randomised placebo-controlled clinical trial it is assumed that psychosocial effects of the treatment, regression to the mean and spontaneous remission are identical in the drug and placebo group. Consequently, any difference between the groups can be ascribed to the pharmacological effects. Previous studies suggest that side effects of drugs can enhance expectancies of treatment effects in the drug group compared to the placebo group, and thereby increase placebo responses in the drug group compared to the placebo group. ⋯ The analgesic effect of caffeine was increased by information that a painkiller was administered. This was due to an interaction of the pharmacological action of the drug and expectancies. Hence, psychosocial effects accompanying a treatment can differ when an active drug is administered compared to a placebo.
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Review
Mephedrone (4-methylmethcathinone; 'meow meow'): chemical, pharmacological and clinical issues.
Recently, those substances deriving from the active ingredient of the Khat plant, cathinone, have been rising in popularity. Indeed, 4-methylmethcathinone (mephedrone; 'meow meow' and others) has been seen by some as a cheaper alternative to other classified recreational drugs. ⋯ Within the UK, diffusion of mephedrone may have been associated with an unprecedented combination of a particularly aggressive online marketing policy and a decreasing availability/purity of both ecstasy and cocaine. Mephedrone has been recently classified in both the UK and in a number of other countries as a measure to control its availability. Following this, a few other research psychoactives have recently entered the online market as yet unregulated substances that may substitute for mephedrone. Only international collaborative efforts may be able to tackle the phenomenon of the regular offer of novel psychoactive drugs.
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Clinical Trial
Subjective and physiological effects of acute intranasal methamphetamine during d-amphetamine maintenance.
Methamphetamine abuse and dependence are significant public-health concerns. Behavioral therapies are effective for reducing methamphetamine use. However, many patients enrolled in behavioral therapies are unable to achieve significant periods of abstinence, suggesting other strategies like pharmacotherapy are needed. ⋯ These results are concordant with those of clinical trials and provide further support for the use of agonist replacement therapy to manage methamphetamine dependence. Additional research in humans is needed to determine the effectiveness of D: -amphetamine under different experimental conditions that more closely reflect use in the natural environment (e.g., higher methamphetamine doses) and behavioral arrangements that are predictive of pharmacotherapy effectiveness (e.g., drug self-administration).
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Extracellular signal-regulated kinase (ERK), cAMP response element binding protein (CREB), and protein kinase B (PKB or Akt) in the striatum are differentially activated by acute and repeated amphetamine (AMPH) administration. However, the dopamine receptor subtypes that mediate transient vs. prolonged phosphorylation changes in these proteins induced by AMPH challenge in AMPH-sensitized rats are unknown. ⋯ These data indicate that the time course of phosphoprotein signaling is differentially regulated by D1 and D2 receptors in the striatum of AMPH-sensitized rats, suggesting that complex regulatory interactions are activated by repeated AMPH exposure.