Figure 5.
Gi/o signaling is required for the impairment of retrieval by xamoterol. Bilateral cannulae targeting the DH were implanted in mice, and one week later the mice were infused with either saline (Sal) or pertussis toxin (PTx, 10 ng/DH). The next day, the mice were fear conditioned, and 2 d later the mice were infused with either vehicle or xamoterol (Xam, 10 µg/DH). Contextual fear was tested 15 min later. Pertussis toxin pretreatment blocked the impairing effect of xamoterol on retrieval, indicating that this effect is mediated by the Gi/o class of G proteins. There were 5 mice per group. F(1,18) = 6.5 and P = 0.021 for the main effect of pretreatment; F(1,18) = 10.1 and P = 0.006 for the main effect of treatment; and F(1,18) = 9.9 and P = 0.006 for the interaction. (∧ = P < 0.01 for post-hoc comparison.)