BST1 and major depressive disorder: To evaluate the predictive validity and the involvement of DA signaling in depression-like behavior in CD157 KO mice, we used 1 mg/kg pramipexole, which is an effective dose in animal models of PD and depression (Maj et al., 1997; Siuciak and Fujiwara, 2004; Kitagawa et al., 2009; Bonito-Oliva et al., 2014).