Effects of hippocampus-induced prefrontal long-term depression on gamma-band local field potential in anesthetized rats.
To determine whether long-term depression (LTD) affects cortical gamma-band local field potential (40-100 Hz), we conducted a LTD induction experiment in the hippocampus-prefrontal cortex (PFC) pathway of an anesthetized rat. The LTD induction increased the spontaneous level of PFC gamma-band power of 70-100 Hz, which was not affected after the long-term potentiation (LTP) induction in our previous experiment. In addition, the LTD induction increased the evoked PFC gamma-band power at 900 ms after hippocampal test stimulation; this latency appeared to differ from that (500-700 ms) observed in our previous LTP experiment. The results indicate that the PFC field potential increases its gamma-band power following both LTP and LTD in the hippocampus-PFC pathway, which is involved in working memory. Particularly, the sustained increase by LTD may reflect a representation of working memory.
Izaki
Yoshinori
Y
Department of Physiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki 216-8511, Japan. yizaki@marianna-u.ac.jp
Takita
Masatoshi
M
Nomura
Masahiko
M
Akema
Tatsuo
T
D000704:Analysis of Variance; D000818:Animals; D004558:Electric Stimulation; D004569:Electroencephalography; D006624:Hippocampus / Q000502:physiology*; D036881:Long-Term Synaptic Depression / Q000502:physiology*; D008297:Male; D009434:Neural Pathways / Q000502:physiology; D009473:Neuronal Plasticity; D017397:Prefrontal Cortex / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar