Fig. 3: Effects of junk-food on CP-AMPAR-mediated transmission and generation of silent synapses in obesity-prone male rats.

a Experimental timeline. CP-AMPAR-mediated transmission and measures of silent synapses were determined following 10 days of junk-food with and without 24–48 h deprivation. b Normalized eEPSC amplitude before and after Naspm (200 µM). Naspm produced similar decreases in eEPSC amplitude in obesity-prone (OP) chow and junk-food groups. However, junk-food deprivation enhanced Naspm sensitivity. The inset shows example traces from chow and junk-food groups before (black) and after bath application of Naspm (red). c Average reduction in eEPSC amplitude in chow and junk-food groups. Junk-food deprivation resulted in enhanced Naspm sensitivity. d Raw eEPSC amplitudes for chow, junk-food, and junk-food deprivation groups. Range of baseline amplitudes does not differ across groups. e The percent of silent synapses in obesity-prone (OP) chow, junk-food, and junk-food deprivation groups. f Representative traces of eEPSCs at +45 (NMDAR mediated) and −70 mV (AMPAR mediated) for junk-food and chow groups. *p < 0.05 chow vs. junk-food, ^#p < 0.05 junk-food vs. junk-food deprivation. g Depiction of recording area within the NAc core.