will take place on Tuesday, October 30, 2018 from 17:15 to 18:15 hours in CBBM, Ground Floor, B1/B2.
Host: Prof. Dr. Markus Schwaninger
Institute of Pharmacology and Toxicology
University of Lübeck
Abstract
Transient receptor potential (TRP) ion channels have been identified as versatile, multimodal molecular sensors. Particularly, several members of the extended TRP ion channel family detect temperature changes in the somatosensory nervous system. Pharmacology and genetic deletion experiments have shown that TRP channels are necessary for mediating responses to painfully hot or cold temperatures and that they become sensitized under inflammatory conditions leading to exacerbated nociceptive signals. TRPs have therefore emerged as targets for analgesic therapy.
Besides constituting a warning system alerting us about noxious thermal conditions, temperature detection in the innocuous range serves another important feat: Mammalian organisms possess the remarkable ability to maintain internal body temperature (Tcore) within a narrow range close to 37°C despite wide environmental temperature variations. The brain’s neural “thermostat” is made up by central circuits in the hypothalamic preoptic area (POA), which orchestrate peripheral thermoregulatory responses to maintain Tcore. How the POA detects and integrates temperature information to achieve thermal balance is largely unknown.
I will begin my presentation by describing some of the classic electrophysiological studies that initially (and historically) have identified and characterized temperature responsive POA neurons. I will then continue by putting our own findings in the context of these previous studies. We have used ex-vivo neuronal preparations in combination with calcium imaging to characterize warmth-sensitive POA neurons. We have also employed manipulations in vivo to asses the physiological role of identified neurons in the context of thermoregulation.
Lastly, I will present preliminary data and give an outlook about future experiments geared to address key questions concerning internal (deep brain) temperature detection and thermoregulation.
Biosketch
Jan Siemens studied Biochemistry in Frankfurt and obtained his PhD in Neuroscience at the Friedrich Miescher Institute Basel, Switzerland/The Scripps Institute, San Diego, USA. After his postdoctoral training at the University of California San Francisco, he returned to German taking up the post of Group Leader at the Max Delbrueck Center in Berlin. Since 2013 he is Professor in the Department of Pharmacology at the University of Heidelberg, Group Leader in the Molecular Medicine Partnership Unit as well as ERC Investigator.
His research focuses on understanding sensory mechanisms at the molecular level and is currently investigating 3 areas in this field:
- Identification and analysis of sensory TRP channel modulators
- Identification of molecules involved in developmental and functional aspects of mechanosensation
- Molecular mechanisms underlying temperature detection and core body temperature regulation
