Translational studies in humans
The examination of altered states of consciousness in healthy volunteers induced by a single application of a hallucinogenic substance has a long history in psychiatric research and has been key to our work in Germany. Through the targeted pharmacological manipulation of a neurotransmitter system in the brain it is possible to elicit symptoms that are to some extent comparable to those observed in patients suffering psychoses. It is then possible to examine the resulting neurobiological changes as well as psychopathological abnormalities, behavioral and cognitive function changes. We exclusively administered exogenous cannabinoids for the induction of altered states of consciousness. Those exogenous cannabinoids exert their effects mainly on the body's own endocannabinoid system. This allowed us to investigate significant effects of this system on the above-mentioned functions. We strived to perform comparable experiments in healthy individuals as we did in our animal experimental approaches. In doing so we attempted to ensure comparability of the respective changes, to the extent this is attainable among different species. This translational approach contributed to a better understanding of the underlying neurobiological processes of endocannabinoidergic functions in psychiatric disorders.
Funding:
This research was supported by the European Commission (GxE Experimental EU FP7 HEALTH-F2-2010-241909).
Publications:
T. Woelfl, C. Rohleder, J. K. Mueller, B. Lange, A. Reuter, A. M. Schmidt, D. Koethe, M. Hellmich, F. M. Leweke: Effects of cannabidiol and delta-9-tetrahydrocannabinol on emotion, cognition and attention: A double-blind, placebo-controlled, randomized experimental trial in healthy volunteers. Front Psychiatry (2020) 11:576877
O. Grimm, M. Löffler, S. Camping, C. Rohleder, F. M. Leweke, H. Flor: Probing the endocannabinoid system in healthy volunteers: cannabidiol alters fronto-striatal resting-state connectivity. Eur Neuropsychopharmacol (2018) 28:841-849
D. Koethe, C. Hoyer, F. M. Leweke: The endocannabinoid system as a target for modelling psychosis. Psychopharmacology (2009) 206: 551-561.
D. Koethe, C. W. Gerth, M. A. Neatby, A. Haensel, C. Mauss, M. Thies, U. Schneider, H. M. Emrich, J. Klosterkötter, F. M. Leweke: Disturbances of visual information processing in early states of psychosis and experimental delta-9-Tetrahydrocannabinol altered states of consciousness. Schizophr Res (2006) 88(1-3):142-150.
D. Koethe, C. W. Gerth, M. A. Neatby, A. Haensel, C. Mauss, M. Thies, U. Schneider, H. M. Emrich, J. Klosterkötter, F. M. Leweke: Disturbances of visual information processing in early states of psychosis and experimental delta-9-Tetrahydrocannabinol altered states of consciousness. Schizophr Res (2006) 88(1-3):142-150.
F. M. Leweke, U. Schneider, M. Radwan, E. Schmidt, H. M. Emrich: Different effects of nabilone and cannabidiol on binocular depth inversion in man. Pharmacol Biochem Behav (2000) 66(1):175-181.
F. M. Leweke, U. Schneider, M. Thies, T. F. Münte, H. M. Emrich: Effects of synthetic ∆9-tetrahydrocannabinol on binocular depth inversion of natural and artificial objects in man. Psychopharmacology (1999) 142:230-235.