Occlusion of low-frequency-induced, heterosynaptic long-term potentiation in the rat hippocampus in vivo following spatial training.

Recent work has shown that some low-frequency stimulation (LFS) protocols can induce long-term potentiation (LTP) at hippocampal synapses. As LFS mimics certain aspects of low-frequency oscillations during slow-wave sleep, LFS-LTP may be relevant to processes of sleep-dependent consolidation. Here, alternating LFS (1 Hz) of heterosynaptic inputs arising in the medial septum and area CA3 induced LTP at hippocampal CA1 synapses of anesthetized rats.

Role of cholinergic-muscarinic receptors in visual discrimination performance of rats: importance of stimulus load.

Central cholinergic transmission has long been implicated in various cognitive processes, including memory acquisition, consolidation, and attentional processes. Here, we examined the role of muscarinic receptors in visual discrimination performance under conditions of altered visual information availability. Adult rats were trained to discriminate two visual cues (indicating the presence and absence of a hidden escape platform, respectively) in a water maze-based, trapezoidal-shaped apparatus.