Science Digest Talk: Distinct behavioral effects of cannabinoids in 3D motion capture of freely moving mice

Speaker: Bogna Ignatowska-Jankowska (Postdoctoral Scholar at Neuronal Rhythms in Movement Unit led by Marylka Yoe Uusisaari)

Abstract:

    One of behavioral effects of cannabinoid CB1 receptor activation is inhibition of locomotor activity. However, effects of endogenous cannabinoids on behavior have not been extensively studied. Here we aimed to assess whether enhancing endocannabinoid signaling produces effects similar to exogenous cannabinoid agonists.
    To elevate signaling of endocannabinoids 2-Arachidonoylglycerol and Anandamide we used selective inhibitors (MJN110 and PF3845, respectively) of Monoacylglycerol lipase and Fatty Acid Amide Hydrolase, enzymes responsible for their degradation. High-speed, high-resolution 3D motion capture system (Qualisys) was used to track movement (3D trajectories and velocity of markers) during voluntary locomotor tasks: open field exploration, vertical and horizontal climbing, beam walking, aerial righting reflex.
    The results revealed distinct behavioral phenotypes induced by different cannabinoids. Low doses of synthetic cannabinoid agonist CP55,940 (0.03, 0.1, 0.3 mg/kg) produced significant bidirectional, task-dependent effects: a decrease of activity and widened stance in the open field, but increased activity in the climbing task (n=10). MJN110 (1.25, 2.5 mg/kg) significantly increased the activity both in the open field and climbing tasks (n=10) and preliminary data indicate this increase is CB1-mediated (n=6). PF3845 did not have a significant effect on activity or gait at the moderate dose (10 mg/kg) and significantly decreased activity at high dose (30 mg/kg).
    The results suggest that selective elevation of 2-AG and AEA signaling results in distinct, bidirectional effects on behavior that are different from exogenous cannabinoid agonists.  Furthermore, the work highlights the strength of 3D motion capture as precise and sensitive tool to evaluate wide range of behaviors in rodents.

Location: C700, Lab3

Zoom: https://oist.zoom.us/j/93174029855, password: 896342