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Xia ZHANG“Astrocytes and memory”

Abstract :

CA1 pyramidal neurons in the hippocampus, which are innervated by glutamatergic CA3 inputs and GABAergic local inputs, make critical contributions to cannabinoid impairment of working memory.
Cannabinoid CB1 receptors (CB1R) are known to exist in these excitatory and inhibitory axonal terminals, but it is not known whether activation of these CB1Rs by cannabinoids impairs working memory. Surprisingly, our recent works suggest that cannabinoids activate CB1R in astroglial cells, but not CB1R in glutamatergic or GABAergic axonal terminals, which leads to induction of long-term depression of excitatory synaptic strength in CA1 area, resulting in cannabinoid impairment of spatial working memory. Some key experiments were actually completed by collaboration with three laboratories in the NeuroCentre Magendie here at Bordeaux.

Selected publications

Han J, Kesner P, Metna-Laurent M, Duan T, Xu L, Georges F, Koehl M, Abrous DN, Mendizabal-Zubiaga J, Grandes P, Liu Q, Bai G, Ren W, Marsicano G*, Zhang X*. Astroglial CB1 receptors mediate in vivo synaptic depression and working memory impairment by acute cannabinoids.
Cell (accepted).

Han J, Liu Z, Ren W, Zhang X*. (2011) Counteractive effects of cannabinoid and nicotine addictive behavior. NeuroReport 22: 181-184.

Scientific focus :

Dr. Xia Zhang, M.D., M.A., Ph.D., is Adjunct Professor in the Department of Psychiatry and the Department of Cellular and Molecular Medicine/University of Ottawa. Dr. Zhang received M.D. (1983) in the 3rd Military Medical University (China). Following his Ph.D. (1992), which was completed at the 4th Military Medical University (China), he served as a Postdoctoral Research Fellow first in the Centre National de la Recherche Scientifique (Paris) (1993) and then in the Department of Psychiatry, University of Saskatchewan (Canada) (1993-1999) before being appointed as assistant professor (1999) and associate professor (2004) in the Department of Psychiatry, University of Saskatchewan (Canada). After his move to the University of Ottawa Institute of Mental Health Research (IMHR) in 2006, Dr. Zhang became the senior scientist of the Translational Neuroscience Unit. Dr. Zhang’s research is to explore how cannabinoids and endocannabinoids modulate reward, memory and mood in animal models. He has published over 70 papers/chapters in peer reviewed journals, including the prestigious journals Nature Medicine, Journal of Clinical Investigation and Journal of Neuroscience. 

Giovanni Marsicano