Figure 6.

Dkk-1 and Wnt1 infusions are not associated with altered fear acquisition, short-term memory, or fear expression. a, Mice were injected via stereotaxically placed cannulae within bilateral amygdala, with vehicle, Dkk-1, or Wnt1 (n = 11 per group) before fear conditioning with 5–6 kHz tone-footshock pairings. No differences were seen in the freezing responses during fear training. b, At 1 h following the above training, mice were tested in a short-term memory paradigm in which 5 tones were presented and freezing was measured. In contrast to the effects of Dkk-1 and Wnt1 on long-term memory consolidation, no differences were seen in this short term memory test. c, Forty-eight hours following training to five tone–shock pairings with a 12 kHz tone, mice were tested for expression of conditioned fear. In this study, mice were injected via cannulae bilaterally into the amygdala, with vehicle (n = 11), Dkk-1 (n = 11), or Wnt1 (n = 11) before testing. No effect of drug was seen on expression of conditioned freezing across three blocks of five tones each.