@article{GeisWeishauptGruenewaldetal.2011,
  author    = {Geis, Christian and Weishaupt, Andreas and Gr{\"u}newald, Benedikt and Wultsch, Thomas and Reif, Andreas and Gerlach, Manfred and Dirkx, Ron and Solimena, Michele and Toyka, Klaus V and Folli, Franco and Perani, Daniela and Heckmann, Manfred and Sommer, Claudia},
  title     = {Human Stiff-Person Syndrome IgG Induces Anxious Behavior in Rats},
  series = {Plos One},
  volume    = {6},
  journal   = {Plos One},
  number    = {2},
  doi       = {10.1371/journal.pone.0016775},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140506},
  pages     = {e16775},
  year      = {2011},
  abstract  = {Background: Anxiety is a heterogeneous behavioral domain playing a role in a variety of neuropsychiatric diseases. While anxiety is the cardinal symptom in disorders such as panic disorder, co-morbid anxious behavior can occur in a variety of diseases. Stiff person syndrome (SPS) is a CNS disorder characterized by increased muscle tone and prominent agoraphobia and anxiety. Most patients have high-titer antibodies against glutamate decarboxylase (GAD) 65. The pathogenic role of these autoantibodies is unclear. Methodology/Principal Findings: We re-investigated a 53 year old woman with SPS and profound anxiety for GABA-A receptor binding in the amygdala with (11) C-flumazenil PET scan and studied the potential pathogenic role of purified IgG from her plasma filtrates containing high-titer antibodies against GAD 65. We passively transferred the IgG fraction intrathecally into rats and analyzed the effects using behavioral and in vivo electrophysiological methods. In cell culture, we measured the effect of patient IgG on GABA release from hippocampal neurons. Repetitive intrathecal application of purified patient IgG in rats resulted in an anxious phenotype resembling the core symptoms of the patient. Patient IgG selectively bound to rat amygdala, hippocampus, and frontal cortical areas. In cultured rat hippocampal neurons, patient IgG inhibited GABA release. In line with these experimental results, the GABA-A receptor binding potential was reduced in the patient's amygdala/hippocampus complex. No motor abnormalities were found in recipient rats. Conclusion/Significance: The observations in rats after passive transfer lead us to propose that anxiety-like behavior can be induced in rats by passive transfer of IgG from a SPS patient positive for anti-GAD 65 antibodies. Anxiety, in this case, thus may be an antibody-mediated phenomenon with consecutive disturbance of GABAergic signaling in the amygdala region.},
  language  = {en}
}
@article{LiuBonalumeGaoetal.2022,
  author    = {Liu, Sheng and Bonalume, Veronica and Gao, Qi and Chen, Jeremy Tsung-Chieh and Rohr, Karl and Hu, Jing and Carr, Richard},
  title     = {Pre-synaptic GABA\(_A\) in NaV1.8\(^+\) primary afferents is required for the development of punctate but not dynamic mechanical allodynia following CFA inflammation},
  series = {Cells},
  volume    = {11},
  journal   = {Cells},
  number    = {15},
  issn      = {2073-4409},
  doi       = {10.3390/cells11152390},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-286081},
  year      = {2022},
  abstract  = {Hypersensitivity to mechanical stimuli is a cardinal symptom of neuropathic and inflammatory pain. A reduction in spinal inhibition is generally considered a causal factor in the development of mechanical hypersensitivity after injury. However, the extent to which presynaptic inhibition contributes to altered spinal inhibition is less well established. Here, we used conditional deletion of GABA\(_A\) in NaV1.8-positive sensory neurons (Scn10a\(^{Cre}\);Gabrb3\(^{fl/fl}\)) to manipulate selectively presynaptic GABAergic inhibition. Behavioral testing showed that the development of inflammatory punctate allodynia was mitigated in mice lacking pre-synaptic GABA\(_A\). Dorsal horn cellular circuits were visualized in single slices using stimulus-tractable dual-labelling of c-fos mRNA for punctate and the cognate c-Fos protein for dynamic mechanical stimulation. This revealed a substantial reduction in the number of cells activated by punctate stimulation in mice lacking presynaptic GABA\(_A\) and an approximate 50\% overlap of the punctate with the dynamic circuit, the relative percentage of which did not change following inflammation. The reduction in dorsal horn cells activated by punctate stimuli was equally prevalent in parvalbumin- and calretinin-positive cells and across all laminae I-V, indicating a generalized reduction in spinal input. In peripheral DRG neurons, inflammation following complete Freund's adjuvant (CFA) led to an increase in axonal excitability responses to GABA, suggesting that presynaptic GABA effects in NaV1.8\(^+\) afferents switch from inhibition to excitation after CFA. In the days after inflammation, presynaptic GABA\(_A\) in NaV1.8\(^+\) nociceptors constitutes an "open gate" pathway allowing mechanoreceptors responding to punctate mechanical stimulation access to nociceptive dorsal horn circuits.},
  language  = {en}
}