Speaker Bio
Tobias Buchborn holds a diploma in Psychology from the Otto-von-Guericke University Magdeburg. He received his PhD in Neurobiology for his research about tolerance to psychedelic drugs at the Institute of Pharmacology and Toxicology in Magdeburg. In 2016, Tobias was awarded an individual Marie-Curie-Skłodowska Fellowship and joined the Laboratory for Neuronal Circuit Dynamics at Imperial College London. Here, he used refined techniques of optogenetic voltage-imaging to investigate how pyramidal cells of the brain cortex orchestrate as mice respond to psychedelic serotonin-2A receptor activation. Since early 2021, Tobias is with the Laboratory for Translational Psychopharmacology at CIMH Mannheim, where he combines behavioural, molecular biological as well as chemo- and optogentic methods to evaluate the applicability of psychedelics in the treatment of addiction.
ICPR 2024 Abstract
The enigmatic psychedelic wet dog shake – Challenging the thalamocortial glutamate hypothesis of psychedelic drug action
Theoretical Background and Rationale: Across mammals, psychedelics induce a complexity of
physiobehavioural effects, which despite the current renaissance of psychedelic research have hardly been integrated into a holistic understanding of what these drugs do to the body fundamentally. The so-called wet dog shake (WDS) for instance is a reliable physiobehavioural concomitant of psychedelic drug action across mammals. Outside of psychedelic drug action, the WDS is a fundamental survival mechanism [1]; within psychedelic drug action, however, its physiological significance remains enigmatic.
Research Question and Hypothesis: The mechanism of action of psychedelic drugs – including
the substrates of WDS – is often discussed in the context of a prominent electrophysiological in vitro
model, which links psychedelic pharmacodynamics to a serotonin2A receptor related glutamate
imbalance in the thalamocortical system [2]. Yet, the in vivo validation of this model has remained a
methodological challenge [3].
Methods and Analysis: Here, we use in vivo fibre photometry employing various genetic probes including GCaMP7 (calcium indicator) and GluSnFR (glutamate-sensitive reporter) expressed in a neuronal-specific manner.
Main Findings: We demonstrate how layer 5 pyramidal cells in the prelimbic cortex, extracellular glutamate levels, and the “thalamic gateway” to the cortex orchestrate as freely moving animals engage in psychedelic-induced WDS.
Conclusion: Currently, psychedelic drugs are tested as psychotherapeutic adjunctive for diverse
psychopathologies. Only by understanding the physiobehavioural properties of these drugs at a
fundamental level, will we be able to truly grasp their therapeutic potential. Here, deciphering the
substrates of WDS should facilitate the understanding of psychedelic drug action as a whole.