Effects of Post-Training Blockade of GABA_B Receptor on Memory of Food Location and Expression of Synapsin I in the Hippocampus of Pigeons (<i>Columba livia</i>)

Abstract

This study investigated effects of post-training treatment with phaclofen, GABA B receptor antagonist, on the memory of food location and on the expression of Synapsin I in the hippocampus of pigeons. Pigeons were trained in food location (7 sessions) and underwent post-training treatment with phaclofen (0.3 mg/kg, i.p.; PHAC), saline (SAL) or non-treated (NTR). Testing for memory persistence occurred 7 days after the last training session (PHACR, SALR and NTRR Groups). Pigeons treated with phaclofen had lower latency and higher correct choice values than saline and non-treated controls ( p < 0.05). Analysis of hippocampus tissue indicated that Synapsin I-positive cell counts were higher in pigeons treated with phaclofen than in saline and non-treated controls ( p < 0.05). Data indicated enhancement of consolidation and persistence of food location memory, and up-regulation of Synapsin I expression in the hippocampus of pigeons, which were related with post-training blockade of GABA B receptors.