title: Somatosensory stimulation suppresses the excitability of pyramidal cells in the hippocampal CA1 region in rats.
abstract: The hippocampal region of the brain is important for encoding environment inputs and memory formation. However, the underlying mechanisms are unclear. To investigate the behavior of individual neurons in response to somatosensory inputs in the hippocampal CA1 region, we recorded and analyzed changes in local field potentials and the firing rates of individual pyramidal cells and interneurons during tail clamping in urethane-anesthetized rats. We also explored the mechanisms underlying the neuronal responses. Somatosensory stimulation, in the form of tail clamping, chan-ged local field potentials into theta rhythm-dominated waveforms, decreased the spike firing of pyramidal cells, and increased interneuron firing. In addition, somatosensory stimulation attenuated orthodromic-evoked population spikes. These results suggest that somatosensory stimulation suppresses the excitability of pyramidal cells in the hippocampal CA1 region. Increased inhibition by local interneurons might underlie this effect. These findings provide insight into the mechanisms of signal processing in the hippocampus and suggest that sensory stimulation might have therapeutic potential for brain disorders associated with neuronal hyperexcitability.
authors.affiliation: Key Laboratory of Biomedical Engineering of Education Ministry, College of Biomedical Engineering and Instrumentation Science, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Biomedical Engineering of Education Ministry, College of Biomedical Engineering and Instrumentation Science, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Zhouyan
authors.initials: Z
authors.lastname: Feng
authors.affiliation: Key Laboratory of Biomedical Engineering of Education Ministry, College of Biomedical Engineering and Instrumentation Science, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Biomedical Engineering of Education Ministry, College of Biomedical Engineering and Instrumentation Science, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Zheng
keywords: 973 Program; excitability; hippocampal CA1 region; local field potential; nerve regeneration; neural regeneration; population spike; somatosensory stimulation; tail clamping; unit spike