Figure 2From: Rapid synaptic potentiation within the anterior cingulate cortex mediates trace fear learningNMDA receptor GluN2B subunit activity is required for trace fear memory. (A) We exposed mice to i.p. injections of either Ro25-6981 or ifenprodil (10 mg/kg @ 2 mg/ml), or saline, 30 min prior to trace fear conditioning and assessed freezing behavior in response to the CS in a new context 48 h later. (B-C) Mice exposed to either Ro25-6981 or ifenprodil prior to training exhibited normal learning behavior but a robust reduction in freezing behavior in response to the CS compared to mice exposed to saline, or to mice exposed to Ro25-6981 30 min prior to testing. (D) Treatment with Ro25-6981 30 min prior to training completely blocked trace fear induced membrane GluA1 upregulation in the ACC (saline: n = 7; Ro25-6981: n = 8; ifenprodil: n = 6; Ro25-6981 at test: n = 5; F = 6.64). (E) Mice displayed similar response latencies in the hot plate (55°C) and tail flick assays when treated with Ro25-6981 or saline 30 min before testing. (* P < 0.02 ).Back to article page