Melamine induced spatial cognitive deficits associated with impairments of hippocampal long-term depression and cholinergic system in Wistar rats

► Investigating rat's cognitive impairment induced by melamine in vivo. ► Performing MWM test, electrophysiological test and ELISA methods. ► Learning and reversal learning abilities were significantly weakened. ► Long-term depression and cholinergic neurotransmission were impaired. ► Poor performance is associated with synaptic plasticity and cholinergic system damage.