CNR1 and Anxiety: Furthermore, considering the possible involvement of brain CB receptors in these NC- and/or IM-induced memory- and anxiety-related behavioral alterations, the effects of selected CB ligands (the CB1 antagonist AM 251, the non-selective CB agonist CP 55,940, and the CB1 partial agonist/antagonist virodhamine) were evaluated against these behavioral alterations, as described in previous studies [43,51,52].