Correction: Electrical Pulse Stimulation of Cultured Human Skeletal Muscle Cells as an In Vitro Model of Exercise.

[This corrects the article DOI: 10.1371/journal.pone.

Electrical pulse stimulation of cultured human skeletal muscle cells as an in vitro model of exercise.

Background And Aims: Physical exercise leads to substantial adaptive responses in skeletal muscles and plays a central role in a healthy life style. Since exercise induces major systemic responses, underlying cellular mechanisms are difficult to study in vivo. It was therefore desirable to develop an in vitro model that would resemble training in cultured human myotubes.

[Gender- and age-related differences in dosage and serum concentration of psychotropic drugs].

Background: The dose recommendations in the Norwegian Pharmaceutical Product Compendium (Felleskatalogen) are not gender-specific, despite evidence of gender-dependent differences in the metabolism of a number of drugs. The purpose of this study was to investigate the extent to which age and gender influence the prescription and serum concentration of psychotropic drugs.

Material And Method: The prescribed doses and serum concentrations of antidepressant, antipsychotic and antiepileptic drugs were studied in relation to age and gender in 1533 patients.

Pharmacokinetic variability of quetiapine and the active metabolite N-desalkylquetiapine in psychiatric patients.

Background: Quetiapine is an atypical antipsychotic drug that was recently also approved for the treatment of uni- and bipolar depression. The antidepressive response is considered to be mediated by the metabolite N-desalkylquetiapine, and the aim of this study was to assess the interindividual pharmacokinetic variability of quetiapine and N-desalkylquetiapine in psychiatric patients based on therapeutic drug monitoring samples.

Methods: Serum measurements of quetiapine and N-desalkylquetiapine performed between October 2007 and July 2008 were retrospectively included from a routine therapeutic drug monitoring database.

Influence of comedication on serum concentrations of aripiprazole and dehydroaripiprazole.

Aripiprazole, a relatively new antipsychotic drug, is metabolized by cytochrome P450 3A4 (CYP3A4) and CYP2D6 to an active metabolite, dehydroaripiprazole. As studies on pharmacokinetic drug interactions with aripiprazole are so far limited, the aim of the present study was to investigate the impact of comedication on serum concentrations of aripiprazole and dehydroaripiprazole in psychiatric patients in a clinical setting. A therapeutic drug monitoring database was screened for patients receiving aripiprazole tablets as part of their treatment.

Metabolism of quetiapine by CYP3A4 and CYP3A5 in presence or absence of cytochrome B5.

The antipsychotic drug quetiapine is extensively metabolized by CYP3A4, but little is known about the possible influence of the polymorphic enzyme CYP3A5. This in vitro study investigated the relative importance of CYP3A4 and CYP3A5 in the metabolism of quetiapine and compared the metabolic pattern by the two enzymes, in the presence or absence of cytochrome b(5). Intrinsic clearance (CL(int)) of quetiapine was determined by the substrate depletion approach in CYP3A4 and CYP3A5 insect cell microsomes with or without coexpressed cytochrome b(5).

Heterozygous mutation in CYP2C19 significantly increases the concentration/dose ratio of racemic citalopram and escitalopram (S-citalopram).

There is limited documentation of the importance of heterozygous cytochrome P450 (CYP) mutations on drug exposure. This study was designed to evaluate the influence of heterozygous mutations in CYP2C19 on the serum concentration of racemic citalopram and escitalopram (S-citalopram). Eighty-three samples from subjects with determined CYP2C19 and CYP2D6 genotype receiving racemic citalopram or S-citalopram as part of their clinical treatment were collected from a routine therapeutic drug monitoring database.