Hyperpolarization-activated currents control the excitability of principal neurons in the basolateral amygdala.
Anxiety is thought to be influenced by neuronal excitability in basolateral nucleus of the amygdala (BLA). However, molecules that are critical for regulating excitability of BLA neurons are yet to be determined. In the present study, we have examined whether hyperpolarization-activated cyclic-nucleotide-gated (HCN) channels, which mediate the depolarizing cation current, can control the neuronal excitability. HCN channel-like activity appeared to be detected in BLA principal neurons. ZD7288, a specific blocker for HCN channels, increased the input resistance of membrane, hyperpolarized resting membrane potential, and enhanced action potential firing in BLA principal neurons. The blockade of HCN channels facilitated temporal summation of repetitively evoked excitatory postsynaptic potentials, suggesting that suppression of HCN channel activity in principal neurons can accelerate the propagation of synaptic responses onto the axon hillock. Thus, our findings have laid foundation for studies to reveal how HCN channel activity in BLA principal neurons regulates anxiety in vivo.
Department of Biology, Kyunghee University, Seoul 130-701, Republic of Korea.
Kyungjoon
K
Park
Sukwon
S
Lee
Shin Jung
SJ
Kang
Sukwoo
S
Choi
Ki Soon
KS
Shin
D000679:Amygdala / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D054815:Cyclic Nucleotide-Gated Cation Channels / Q000378:metabolism; D019706:Excitatory Postsynaptic Potentials; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D008297:Male; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D054815:Cyclic Nucleotide-Gated Cation Channels; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D015221:Potassium Channels