title: HCN channel activity-dependent modulation of inhibitory synaptic transmission in the rat basolateral amygdala.
abstract: Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are expressed in the central nervous system and play a regulatory role in neuronal excitability. In the present study, we examined a physiological role of HCN channels in the rat basolateral amygdala (BLA). In vitro electrophysiological studies showed that ZD7288 decreased spontaneous inhibitory postsynaptic current (sIPSC) without changing miniature IPSC (mIPSC). HCN channel blockade also attenuated feedback inhibitions in BLA principal neurons. However, blockade of HCN channel had little effects on spontaneous excitatory postsynaptic current (sEPSC) and mEPSC. Therefore, HCN channel appeared to decrease BLA excitability by increasing the action potential-dependent inhibitory control over the BLA principal neurons. Anxiety is reported to be influenced by neuronal excitability in the BLA and inhibitory synaptic transmission is thought to play a pivotal role in regulating overall excitability of the amygdala. As expected, blockade of HCN channels by targeted injection of ZD7288 to the BLA increased anxiety-like behavior under elevated plus maze test. Our results suggest that HCN channel activity can modulate the GABAergic synaptic transmission in the BLA, which in turn control the amygdala-related emotional behaviors such as anxiety.
authors.affiliation: Department of Biology, Department of Life and Nanopharmaceutical Sciences, Kyunghee University, Seoul 130-701, Republic of Korea.
authors.forename: Kyungjoon
authors.initials: K
authors.lastname: Park
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Yi
authors.forename: Hyejin
authors.initials: H
authors.lastname: Kim
authors.forename: Kyuhyun
authors.initials: K
authors.lastname: Choi
authors.forename: Shin Jung
authors.initials: SJ
authors.lastname: Kang
authors.forename: Ki Soon
authors.initials: KS
authors.lastname: Shin
mesh_terms: D000679:Amygdala / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D001007:Anxiety / Q000503:physiopathology*; D054815:Cyclic Nucleotide-Gated Cation Channels / Q000037:antagonists & inhibitors / Q000502:physiology*; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D018782:Maze Learning; D015221:Potassium Channels / Q000502:physiology*; D011743:Pyrimidines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*
chemical_list: D054815:Cyclic Nucleotide-Gated Cation Channels; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D015221:Potassium Channels; D011743:Pyrimidines; C082246:ICI D2788