CCK IN ANXIETY AND COGNITIVE-PROCESSES

Extensive studies were carried out on the involvement of the CCKergic system in anxiety-, panic- and stress-related behaviour. The stimulati on of CCK-A or CCK-B receptors is implicated in the physical and psych ological responses of CCK to stress. Furthermore, several selective CC K-B agonists produce anxiogenic-like effects, while CCK-B antagonists induce anxiolytic-like responses in several models of anxiety. However , BC264 a highly selective CCK-B agonist, does not produce anxiogenic- like effects but increases attention and/or memory. These effects are dependent on the dopaminergic systems. Together with biochemical data, this led to the hypothesis of the existence of two CCK-B binding site s, CCK-B1 and CCK-B2, which could correspond to different activation s tates of a single molecular entity. Investigations into CCK-B I and CC K-B2 systems might be of critical interest, since only one site, CCK-B 1, appears to be responsible for the effects on anxiety. Furthermore, the improvement of attention and/or memory processes by CCK, through C CK-B2 receptors, could offer a new perspective in the treatment of att ention and/or memory disorders. (C) 1998 Elsevier Science Ltd. All rig hts reserved.