CCK and Anxiety: However, rats with a high‐anxiety phenotype displayed increased expression of CCKBR in the BLA,136 and intra‐BLA injections of a CCKBR agonist increased acoustic startle responses.137 In fear‐conditioning paradigms, IP injections of CCKBR antagonists blocked fear expression and facilitated extinction.138 Collectively, CCK increases anxiety and fear‐related behaviors and can even induce panic attacks (Table 1).