Search results for "serotonin"
showing 10 items of 414 documents
Comparison of the anticonstrictor action of dihydropyridines (nimodipine and nicardipine) and Mg2+ in isolated human cerebral arteries.
1992
The isometric tension recorded from ring segments of branches of human middle cerebral artery was the parameter used to study the inhibition of spasmogen-induced contractions as model for cerebral vasospasm. Concentration-response curves to 5-hydroxytryptamine (10(-9)-3 x 10(-5) M) and prostaglandin F2 alpha (10(-7)-3 x 10(-5) M) were inhibited in Ca(2+)-free medium and in Ca(2+)-free medium to which EGTA (1 mM) had been added, respectively. Nimodipine (10(-7), 10(-5) M), nicardipine (10(-7), 10(-5) M) and Mg2+ (magnesium sulfate 10(-4), 10(-2) M) inhibited the 5-HT-elicited contractions, and this inhibition was similar for the highest concentrations tested. In contrast, nimodipine and nica…
Increased visual cortical excitability in ecstasy users: a transcranial magnetic stimulation study
2003
To test the presence of abnormalities of visual cortical excitability in people using ecstasy as a recreational drug.Ecstasy users and control subjects underwent single pulse transcranial magnetic stimulation (TMS) of the occipital cortex. The phosphene threshold was analysed and compared in the two groups.Phosphene thresholds were significantly lower in ecstasy users compared with control subjects, and were correlated negatively with frequency of ecstasy use. Frequency of use was positively correlated with the presence of visual hallucinations. The phosphene threshold of subjects with hallucinations was significantly lower than that of subjects without hallucinations.The use of ecstasy as …
Melperone is an Inhibitor of the CYP2D6 Catalyzed O-demethylation of Venlafaxine
2003
INTRODUCTION Melperone, a butyrophenone neuroleptic, is frequently used for its sleep-inducing properties. Despite its common use for more than 30 years, it is not yet characterized regarding its effects on cytochrome P450 s (CYPs). In an open pilot study, effects of melperone on the steady-state blood levels of venlafaxine, a recently introduced serotonin- and noradrenaline reuptake inhibiting antidepressant, were assessed. METHODS The dose-corrected serum concentrations of venlafaxine and O-desmethylvenlafaxine were analyzed retrospectively in a therapeutic drug-monitoring (TDM) database comprising 94 patients. In addition, three patients received venlafaxine and melperone concomitantly a…
Conventional and spectral power analysis of all-night sleep EEG after subchronic treatment with paroxetine in healthy male volunteers.
1998
Paroxetine is a selective and potent serotonin reuptake inhibitor with reported antidepressant properties. Since changes in the regular sleeping pattern were described as side effects under treatment with paroxetine, the impact of the drug on the sleep architecture is of major interest. The present study addressed the question of subchronic effects of paroxetine medication (30 mg/day) in eight healthy male volunteers in a double blind, placebo-controlled crossover-design. Conventional sleep EEG parameters and additionally computed spectral power analysis based on FFT of 20-s time epochs in the delta, theta, alpha, beta and gamma frequency range for different sleep stages after 4 weeks of tr…
Time Course of 5-HT2A Receptor Occupancy in the Human Brain after a Single Oral Dose of the Putative Antipsychotic Drug MDL 100,907 Measured by Posit…
1997
MDL 100,907 is a potent and selective antagonist of 5-HT2A serotonin receptors. Animals studies suggest that MDL 100,907 may behave as an atypical antipsychotic drug. Positron emission tomograph (PET) using [11C]NMSP as the radiotracer was used to define the time course of 5-HT2 receptor occupancy in the human frontal cerebral cortex after a single oral dose of MDL 100,907 (10 or 20 mg) in nine healthy subjects. After the baseline scan each subject was studied three times post dosing at various time points. 5-HT2 occupancies were in the range of 70 and 90% after each dose. While the occupancy remains in this range over 24 hours after 20 mg MDL 100,907, it decreases by about 20% at 24 hours …
Testosterone and aggressiveness.
2003
Aggressiveness is an ancestral behavior common to all animal species. Its neurophysiological mechanisms are similar in all vertebrates. Males are generally more aggressive than females. In this review, aggressive behavior in rodents, monkeys, and man and the role of testosterone and brain serotonin levels have been considered. Interspecifi c aggressiveness in rats has been studied considering the mouse-killing behavior; the neonatal androgenization of females increases adult mousekilling as does the administration of testosterone in adults. Intraspecifi c aggressiveness was studied by putting two or more male rats (or mice) in the same cage; the condition of subjection or dominance is infl …
Effects of subchronic paroxetine administration on night-time endocrinological profiles in healthy male volunteers
2000
Abstract To evaluate the subchronic effects of paroxetine, a selective serotonin reuptake inhibitor, on nocturnal endocrinological profiles, eight healthy male volunteers with no personal or family history of a psychiatric or neurological disease were administered paroxetine (30 mg/day) or placebo in a double-blind cross-over design. Drugs were given as a single dose at 10:00 h for a period of 4 weeks each. Between days 21 and 28 of each treatment period, sleep EEG was registered for four consecutive nights from 23:00 to 07:00 h. During the last night, hormonal profiles for prolactin, growth hormone (GH), cortisol, corticotropin (ACTH), luteinizing hormone (LH), testosterone and melatonin w…
Early improvement under mirtazapine and paroxetine predicts later stable response and remission with high sensitivity in patients with major depressi…
2003
OBJECTIVE Current clinical knowledge holds that antidepressants have a delayed onset of efficacy. However, the delayed onset hypothesis has been questioned recently by survival analytical approaches. We aimed to test whether early improvement under antidepressant treatment is a clinically useful predictor of later stable response and remission. METHOD We analyzed data from a randomized double-blind controlled trial with mirtazapine and paroxetine in patients with major depression (DSM-IV). Improvement was defined as a 17-item Hamilton Rating Scale for Depression (HAM-D-17) score reduction of > or = 20%. Stable response was defined as > or = 50% HAM-D-17 score reduction at week 4 and week 6,…
Compliance to therapy with Dapoxetine in patients affected by Premature Ejaculation
2012
Introduction Premature ejaculation (PE) is a sexual dysfunction with high prevalence. According to some reports, it is present in about 20-30% of the male population. Since 2009 PE has been treated with a novel inhibitor of serotonin re-uptake, Dapoxetine, which has been reported to be specifically active for PE. Materials and Methods 59 patients have been selected among the patients affected by PE observed at the outpatient department of Urology and Andrology of the “Paolo Giaccone” University Policlinic Hospital of Palermo. Diagnosis was confirmed unequivocally in all patients, who were suitable for drug treatment and accepted to participate in the study. They were divided in 2 groups: on…
Clinical responses to antidepressants among 1036 acutely depressed patients with bipolar or unipolar major affective disorders.
2012
Whether responses to antidepressants differ in bipolar and unipolar depression remains unresolved.We analyzed patient characteristics and outcomes of antidepressant treatment of 1036 depressed patients with bipolar-I or bipolar-II disorder, or unipolar major depression, using bivariate and multivariate methods and survival analysis, testing the hypothesis that responses would be superior in unipolar depression.Antidepressants were given to 84.8% (878/1036) of depressed patients: 58.9% of 93 bipolar-I, 80.1% of 117 bipolar-II, and 91.3% of 668 unipolar disorder cases. The 158 not given antidepressants had more manias/year, spent more months in mania and depression, and were far more likely t…