@article{GutknechtPoppWaideretal.2015,
  author    = {Gutknecht, Lise and Popp, Sandy and Waider, Jonas and Sommerlandt, Frank M. J. and G{\"o}ppner, Corinna and Post, Antonia and Reif, Andreas and van den Hove, Daniel and Strekalova, Tatyana and Schmitt, Angelika and Colaςo, Maria B. N. and Sommer, Claudia and Palme, Rupert and Lesch, Klaus-Peter},
  title     = {Interaction of brain 5-HT synthesis deficiency, chronic stress and sex differentially impact emotional behavior in Tph2 knockout mice},
  series = {Psychopharmacology},
  volume    = {232},
  journal   = {Psychopharmacology},
  doi       = {10.1007/s00213-015-3879-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-154586},
  pages     = {2429 -- 2441},
  year      = {2015},
  abstract  = {Rationale While brain serotonin (5-HT) function is implicated in gene-by-environment interaction (GxE) impacting the vulnerability-resilience continuum in neuropsychiatric disorders, it remains elusive how the interplay of altered 5-HT synthesis and environmental stressors is linked to failure in emotion regulation. Objective Here, we investigated the effect of constitutively impaired 5-HT synthesis on behavioral and neuroendocrine responses to unpredictable chronic mild stress (CMS) using a mouse model of brain 5-HT deficiency resulting from targeted inactivation of the tryptophan hydroxylase-2 (Tph2) gene. Results Locomotor activity and anxiety- and depression-like behavior as well as conditioned fear responses were differentially affected by Tph2 genotype, sex, and CMS. Tph2 null mutants (Tph2\(^{-/-}\)) displayed increased general metabolism, marginally reduced anxiety- and depression-like behavior but strikingly increased conditioned fear responses. Behavioral modifications were associated with sex-specific hypothalamic-pituitary-adrenocortical (HPA) system alterations as indicated by plasma corticosterone and fecal corticosterone metabolite concentrations. Tph2\(^{-/-}\) males displayed increased impulsivity and high aggressiveness. Tph2\(^{-/-}\) females displayed greater emotional reactivity to aversive conditions as reflected by changes in behaviors at baseline including increased freezing and decreased locomotion in novel environments. However, both Tph2\(^{-/-}\) male and female mice were resilient to CMS-induced hyperlocomotion, while CMS intensified conditioned fear responses in a GxE-dependent manner. Conclusions Our results indicate that 5-HT mediates behavioral responses to environmental adversity by facilitating the encoding of stress effects leading to increased vulnerability for negative emotionality.},
  language  = {en}
}
@article{IpIsaiasKuscheTekinetal.2016,
  author    = {Ip, Chi Wang and Isaias, Ioannis U. and Kusche-Tekin, Burak B. and Klein, Dennis and Groh, Janos and O´Leary, Aet and Knorr, Susanne and Higuchi, Takahiro and Koprich, James B. and Brotchie, Jonathan M. and Toyka, Klaus V. and Reif, Andreas and Volkmann, Jens},
  title     = {Tor1a+/- mice develop dystonia-like movements via a striatal dopaminergic dysregulation triggered by peripheral nerve injury},
  series = {Acta Neuropathologica Communications},
  volume    = {4},
  journal   = {Acta Neuropathologica Communications},
  number    = {108},
  doi       = {10.1186/s40478-016-0375-7},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147839},
  year      = {2016},
  abstract  = {Isolated generalized dystonia is a central motor network disorder characterized by twisted movements or postures. The most frequent genetic cause is a GAG deletion in the Tor1a (DYT1) gene encoding torsinA with a reduced penetrance of 30-40 \% suggesting additional genetic or environmental modifiers. Development of dystonia-like movements after a standardized peripheral nerve crush lesion in wild type (wt) and Tor1a+/- mice, that express 50 \% torsinA only, was assessed by scoring of hindlimb movements during tail suspension, by rotarod testing and by computer-assisted gait analysis. Western blot analysis was performed for dopamine transporter (DAT), D1 and D2 receptors from striatal and quantitative RT-PCR analysis for DAT from midbrain dissections. Autoradiography was used to assess the functional DAT binding in striatum. Striatal dopamine and its metabolites were analyzed by high performance liquid chromatography. After nerve crush injury, we found abnormal posturing in the lesioned hindlimb of both mutant and wt mice indicating the profound influence of the nerve lesion (15x vs. 12x relative to control) resembling human peripheral pseudodystonia. In mutant mice the phenotypic abnormalities were increased by about 40 \% (p < 0.05). This was accompanied by complex alterations of striatal dopamine homeostasis. Pharmacological blockade of dopamine synthesis reduced severity of dystonia-like movements, whereas treatment with L-Dopa aggravated these but only in mutant mice suggesting a DYT1 related central component relevant to the development of abnormal involuntary movements. Our findings suggest that upon peripheral nerve injury reduced torsinA concentration and environmental stressors may act in concert in causing the central motor network dysfunction of DYT1 dystonia.},
  language  = {en}
}