The hippocampus expresses high levels of CB1 receptors in different cell types. Hippocampal circuits formed by different cells, including neuronal and non-neuronal, play a crucial role in cognitive processes such as navigation or memory. In this work, we want to dissect the specific and sex-dependent role of CB1 signalling in different cell types and the impact on hippocampal functions. 

We used genetic tools to perform a specific Cre-mediated CB1 deletion on neurons (excitatory and inhibitory), astrocytes, or interneurons in CB1-flox males and females. Viral vectors (AAV-Cre) were injected bilaterally into the hippocampus of these mice. We used the Barnes maze test to assess cognitive performance (e.g., learning, memory, navigation) and the Novel Object Recognition Test (NORT, recognition memory). In addition, a battery of anxiety-like behavioural protocols was performed before cognitive evaluation to establish an emotional baseline for each animal. 

Our results show that the CB1 receptor action in hippocampal circuits is sex and cell-type dependent.

More information:

• https://www.achucarro.org/laboratory/cellular-basis-of-behavior-and-disease/