A model of synaptic plasticity: activation of mGluR I induced long-term theta oscillations in medial septal diagonal band of rat brain slice.
This study aimed to establish a model of synaptic plasticity by the activation of metabotropic glutamate receptor (mGluR) I in rat medial septal diagonal band (MSDB). Electrophysiological experiment was performed to record the theta frequency oscillation activities in rat MSDB slices. The data were recorded and analyzed with Spike 2 (CED, Cambridge, UK). Application of aminocyclopentane-1, 3-dicarboxylic acid (ACPD) to MSDB slices produced theta frequency oscillations (4-12 Hz) which persisted for hours after ACPD washout, suggesting the existence of a form of synaptic plasticity in long-term oscillations (LTOs). Addition of NMDA receptor antagonist AP5 (50 μM) caused no significant change in area power. In contrast, AMPA/Kainate receptor antagonist NBQX administration partially reduced the area power. Infusion of ZD7288, a hyperpolarization-activated channel (Ih) inhibitor, caused additional reduction to control level. Comparable effects were also observed with administration of DHPG (3, 5-dihydroxyphenylglycine) which also elicited LTOs. mGluR I activation induced theta oscillation and this activity maintained hours after drug washout. Both AMPA and hyperpolarization-activated channel make an essential contribution to LTO. Our study herein established a model of synaptic plasticity.
Department of Physiology and Neurobiology, Xinxiang Medical University, Xinxiang, Henan Province, People's Republic of China.
Chengzhang
C
Li
Zhiyue
Z
Guo
Yali
Y
Wang
Xiaojuan
X
Li
Zainb
Z
Henderson
Cheng B
CB
Lu
D000818:Animals; D001921:Brain / Q000502:physiology; D008297:Male; D008959:Models, Neurological; D009473:Neuronal Plasticity; D051381:Rats; D017208:Rats, Wistar; D018094:Receptors, Metabotropic Glutamate / Q000502:physiology*; D012686:Septal Nuclei / Q000502:physiology*; D013826:Theta Rhythm
D018094:Receptors, Metabotropic Glutamate; C104077:metabotropic glutamate receptor type 1