TY - JOUR A1 - Chen, Y. A1 - Palm, F. A1 - Lesch, K. P. A1 - Gerlach, M. A1 - Moessner, R. A1 - Sommer, C. T1 - 5-hydroxyindolacetic acid (5-HIAA), a main metabolite of serotonin, is responsible for complete Freund's adjuvant-induced thermal hyperalgesia in mice N2 - Background: The role of serotonin (5-hydroxytrptamine, 5-HT) in the modulation of pain has been widely studied. Previous work led to the hypothesis that 5-hydroxyindolacetic acid (5-HIAA), a main metabolite of serotonin, might by itself influence pain thresholds. Results: In the present study, we investigated the role of 5-HIAA in inflammatory pain induced by intraplantar injection of complete Freund’s adjuvant (CFA) into the hind paw of mice. Wild-type mice were compared to mice deficient of the 5-HT transporter (5-HTT-/- mice) using behavioral tests for hyperalgesia and high-performance liquid chromatography (HPLC) to determine tissue levels of 5-HIAA. Wild-type mice reproducibly developed thermal hyperalgesia and paw edema for 5 days after CFA injection. 5-HTT-/- mice treated with CFA had reduced thermal hyperalgesia on day 1 after CFA injection and normal responses to heat hereafter. The 5-HIAA levels in spinal cord and sciatic nerve as measured with HPLC were lower in 5-HTT-/- mice than in wild-type mice after CFA injection. Pretreatment of wild-type mice with intraperitoneal injection of para-chlorophenylalanine (p-CPA), a serotonin synthesis inhibitor, resulted in depletion of the 5-HIAA content in spinal cord and sciatic nerve and decrease in thermal hyperalgesia in CFA injected mice. The application of exogenous 5-HIAA resulted in potentiation of thermal hyperalgesia induced by CFA in 5-HTT-/- mice and in wild-type mice pretreated with p- CPA, but not in wild-type mice without p-CPA pretreatment. Further, methysergide, a broad-spectrum serotonin receptor antagonist, had no effect on 5-HIAA-induced potentiation of thermal hyperalgesia in CFA-treated wildtype mice. Conclusion: Taken together, the present results suggest that 5-HIAA plays an important role in modulating peripheral thermal hyperalgesia in CFA induced inflammation, probably via a non-serotonin receptor mechanism. KW - Medizin Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68858 ER - TY - JOUR A1 - Fekete, Stefanie A1 - Egberts, K. A1 - Preissler, T. A1 - Wewetzer, C. A1 - Mehler-Wex, C. A1 - Romanos, M. A1 - Gerlach, M. T1 - Estimation of a preliminary therapeutic reference range for children and adolescents with tic disorders treated with tiapride JF - European Journal of Clinical Pharmacology N2 - Purpose Tiapride is commonly used in Europe for the treatment of tics. The aim of this study was to examine the relationship between dose and serum concentrations of tiapride and potential influential pharmacokinetic factors in children and adolescents. In addition, a preliminary therapeutic reference range for children and adolescents with tics treated with tiapride was calculated. Methods Children and adolescents treated with tiapride at three university hospitals and two departments of child and adolescents psychiatry in Germany and Austria were included in the study. Patient characteristics, doses, serum concentrations, and therapeutic outcome were assessed during clinical routine care using standardised measures. Results In the 49 paediatric patients (83.7% male, mean age = 12.5 years), a positive correlation was found between tiapride dose (median 6.9 mg/kg, range 0.97–19.35) and serum concentration with marked inter-individual variability. The variation in dose explained 57% of the inter-patient variability in tiapride serum concentrations; age, gender, and concomitant medication did not contribute to the variability. The symptoms improved in 83.3% of the patients. 27.1% of the patients had mild or moderate ADRs. No patient suffered from severe ADRs. Conclusions This study shows that tiapride treatment was effective and safe in most patients with tics. Compared with the therapeutic concentration range established for adults with Chorea Huntington, our data hinted at a lower lower limit (560 ng/ml) and similar upper limit (2000 ng/ml). KW - Tourette syndrome KW - therapeutic drug monitoring KW - serum concentration KW - paediatrics KW - pharmacokinetics Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-279893 VL - 77 IS - 2 ER - TY - GEN A1 - Fekete, Stefanie A1 - Egberts, K. A1 - Preissler, T. A1 - Wewetzer, C. A1 - Mehler-Wex, C. A1 - Romanos, M. A1 - Gerlach, M. T1 - Correction to: Estimation of a preliminary therapeutic reference range for children and adolescents with tic disorders treated with tiapride T2 - European Journal of Clinical Pharmacology N2 - Correction to: European Journal of Clinical Pharmacology (2021) 77:163–170 https://doi.org/10.1007/s00228-020-03000-0 KW - Erratum Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-329467 VL - 77 IS - 8 ER - TY - JOUR A1 - Taurines, R. A1 - Fekete, S. A1 - Preuss-Wiedenhoff, A. A1 - Warnke, A. A1 - Wewetzer, C. A1 - Plener, P. A1 - Burger, R. A1 - Gerlach, M. A1 - Romanos, M. A1 - Egberts, K. M. T1 - Therapeutic drug monitoring in children and adolescents with schizophrenia and other psychotic disorders using risperidone JF - Journal of Neural Transmission N2 - Risperidone is commonly used to treat different psychiatric disorders worldwide. Knowledge on dose–concentration relationships of risperidone treatment in children and adolescents with schizophrenia or other psychotic disorders is, however, scarce and no age-specific therapeutic ranges have been established yet. Multicenter data of a therapeutic drug monitoring service were analyzed to evaluate the relationship between risperidone dose and serum concentration of the active moiety (risperidone (RIS) plus its main metabolite 9-hydroxyrisperidone (9-OH-RIS)) in children and adolescents with psychotic disorders. Patient characteristics, doses, serum concentrations and therapeutic outcomes were assessed by standardized measures. The study also aimed to evaluate whether the therapeutic reference range for adults (20–60 ng/ml) is applicable for minors. In the 64 patients (aged 11–18 years) included, a positive correlation between daily dose and the active moiety (RIS\(_{am}\)) concentration was found (r\(_s\) = 0.49, p = 0.001) with variation in dose explaining 24% (r\(_s\)\(^2\) = 0.240) of the variability in serum concentrations. While the RIS\(_{am}\) concentration showed no difference, RIS as well 9-OH-RIS concentrations and the parent to metabolite ratio varied significantly in patients with co-medication of a CYP2D6 inhibitor. Patients with extrapyramidal symptoms (EPS) had on average higher RIS\(_{am}\) concentrations than patients without (p = 0.05). Considering EPS, the upper threshold of the therapeutic range of RIS\(_{am}\) was determined to be 33 ng/ml. A rough estimation method also indicated a possibly decreased lower limit of the preliminary therapeutic range in minors compared to adults. These preliminary data may contribute to the definition of a therapeutic window in children and adolescents with schizophrenic disorders treated with risperidone. TDM is recommended in this vulnerable population to prevent concentration-related adverse drug reactions. KW - risperidone KW - children KW - serum concentration KW - schizophrenia KW - therapeutic drug monitoring KW - pharmacovigilance Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324833 VL - 129 IS - 5-6 ER -