LTP induction modifies functional relationship among hippocampal neurons.

To obtain evidence linking long-term potentiation (LTP) and memory, we examined whether LTP induction modifies functional relationship among neurons in the rat hippocampus. In contrast to neurons in low-frequency stimulated or AP5-treated slices, LTP induction altered 'functional connectivity,' as defined by the degree of synchronous firing, among simultaneously recorded neurons in the CA3 region. Interestingly, functional connectivity changed bidirectionally so that the total sum of functional connectivity remained constant.

Lithium attenuates stress-induced impairment of long-term potentiation induction.

Stress impairs the induction of long-term potentiation in the hippocampus as well as hippocampus-dependent memory. Lithium, a classical mood stabilizer, is known to have beneficial effects on stress-induced impairment of spatial memory. In the present study, we investigated lithium effects on the impairment of long-term potentiation induction after exposure to acute immobilization stress.