1
|
Al-Owais MM, Hettiarachchi NT, Dallas ML, Scragg JL, Lippiat JD, Holden AV, Steele DS, Peers C. Inhibition of the voltage-gated potassium channel Kv1.5 by hydrogen sulfide attenuates remodeling through S-nitrosylation-mediated signaling. Commun Biol 2023; 6:651. [PMID: 37336943 PMCID: PMC10279668 DOI: 10.1038/s42003-023-05016-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 06/05/2023] [Indexed: 06/21/2023] Open
Abstract
The voltage-gated K+ channel plays a key role in atrial excitability, conducting the ultra-rapid rectifier K+ current (IKur) and contributing to the repolarization of the atrial action potential. In this study, we examine its regulation by hydrogen sulfide (H2S) in HL-1 cardiomyocytes and in HEK293 cells expressing human Kv1.5. Pacing induced remodeling resulted in shorting action potential duration, enhanced both Kv1.5 channel and H2S producing enzymes protein expression in HL-1 cardiomyocytes. H2S supplementation reduced these remodeling changes and restored action potential duration through inhibition of Kv1.5 channel. H2S also inhibited recombinant hKv1.5, lead to nitric oxide (NO) mediated S-nitrosylation and activated endothelial nitric oxide synthase (eNOS) by increased phosphorylation of Ser1177, prevention of NO formation precluded these effects. Regulation of Ikur by H2S has important cardiovascular implications and represents a novel and potential therapeutic target.
Collapse
Affiliation(s)
- Moza M Al-Owais
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
| | - Nishani T Hettiarachchi
- Division of Cardiovascular and Diabetes Research, LICAMM, Faculty of Medicine and Health, University of Leeds, Leeds, LS2 9JT, UK
| | - Mark L Dallas
- Reading School of Pharmacy, University of Reading, Reading, RG6 6UB, UK
| | - Jason L Scragg
- Division of Cardiovascular and Diabetes Research, LICAMM, Faculty of Medicine and Health, University of Leeds, Leeds, LS2 9JT, UK
| | - Jonathan D Lippiat
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Arun V Holden
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Derek S Steele
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Chris Peers
- Division of Cardiovascular and Diabetes Research, LICAMM, Faculty of Medicine and Health, University of Leeds, Leeds, LS2 9JT, UK
| |
Collapse
|
2
|
Pirtle TJ. A review of the circuit-level and cellular mechanisms contributing to locomotor acceleration in the marine mollusk Clione limacina. Front Neurosci 2022; 16:1072974. [PMID: 36620465 PMCID: PMC9815461 DOI: 10.3389/fnins.2022.1072974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022] Open
Abstract
The pteropod mollusk, Clione limacina, is a useful model system for understanding the neural basis of behavior. Of particular interest are the unique swimming behavior and neural circuitry that underlies this swimming behavior. The swimming system of Clione has been studied by two primary groups-one in Russia and one in the United States of America-for more than four decades. The neural circuitry, the cellular properties, and ion channels that create and change the swimming locomotor rhythm of Clione-particularly mechanisms that contribute to swimming acceleration-are presented in this review.
Collapse
Affiliation(s)
- Thomas J. Pirtle
- Department of Biology, The College of Idaho, Caldwell, ID, United States
| |
Collapse
|
3
|
Chen Y, Zhu Z, Tian Y, Jiang L. Rational ion transport management mediated through membrane structures. EXPLORATION 2021; 1:20210101. [PMCID: PMC10190948 DOI: 10.1002/exp.20210101] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/13/2021] [Indexed: 06/14/2023]
Affiliation(s)
- Yupeng Chen
- Key Laboratory of Bio‐Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry Beihang University Beijing P. R. China
| | - Zhongpeng Zhu
- Key Laboratory of Bio‐Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry Beihang University Beijing P. R. China
| | - Ye Tian
- CAS Key Laboratory of Bio‐Inspired Materials and Interfacial Science CAS Center for Excellence in Nanoscience Technical Institute of Physics and Chemistry, Chinese Academy of Sciences Beijing P. R. China
- University of Chinese Academy of Sciences Beijing P. R. China
| | - Lei Jiang
- Key Laboratory of Bio‐Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry Beihang University Beijing P. R. China
- CAS Key Laboratory of Bio‐Inspired Materials and Interfacial Science CAS Center for Excellence in Nanoscience Technical Institute of Physics and Chemistry, Chinese Academy of Sciences Beijing P. R. China
- University of Chinese Academy of Sciences Beijing P. R. China
- School of Future Technology University of Chinese Academy of Sciences Beijing P. R. China
| |
Collapse
|
4
|
Yamashita K, Sundaram P, Uchida T, Matsuo T, Wong W. Modelling the visual response to an OUReP retinal prosthesis with photoelectric dye coupled to polyethylene film. J Neural Eng 2021; 18. [PMID: 33857924 DOI: 10.1088/1741-2552/abf892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 04/15/2021] [Indexed: 11/12/2022]
Abstract
Objective.Retinal prostheses have been developed to restore vision in blind patients suffering from diseases like retinitis pigmentosa.Approach.A new type of retinal prosthesis called the Okayama University-type retinal prosthesis (OUReP) was developed by chemically coupling photoelectric dyes to a polyethylene film surface. The prosthesis works by passively generating an electric potential when stimulated by light. However, the neurophysiological mechanism of how OUReP stimulates the degenerated retina is unknown.Main results.Here, we explore how the OUReP affects retinal tissues using a finite element model to solve for the potential inside the tissue and an active Hodgkin-Huxley model based on rat vision to predict the corresponding retinal bipolar response.Significance.We show that the OUReP is likely capable of eliciting responses in retinal bipolar cells necessary to generate vision under most ambient conditions.
Collapse
Affiliation(s)
- Koichiro Yamashita
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
| | - Prathima Sundaram
- Department of Electrical and Computer Engineering, University of Toronto, 40 St. George Street, Toronto, ON M5S 2E4, Canada
| | - Tetsuya Uchida
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
| | - Toshihiko Matsuo
- Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Willy Wong
- Department of Electrical and Computer Engineering, University of Toronto, 40 St. George Street, Toronto, ON M5S 2E4, Canada
| |
Collapse
|
5
|
Hawkins RD, Kandel ER. Comparison of the ionic currents modulated during activity-dependent and normal presynaptic facilitation. ACTA ACUST UNITED AC 2019; 26:449-454. [PMID: 31615856 PMCID: PMC6796788 DOI: 10.1101/lm.049916.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 08/20/2019] [Indexed: 11/30/2022]
Abstract
One of the major questions in psychology is whether associative and nonassociative learning are fundamentally different or whether they involve similar processes and mechanisms. We have addressed this question by comparing mechanisms of a nonassociative form of learning, sensitization, and an associative form of learning, classical conditioning of the siphon-withdrawal reflex of hermaphroditic Aplysia. In an analog of differential conditioning, action potentials in one siphon sensory neuron (SN) were paired with shock to the pedal nerves, producing activity-dependent presynaptic facilitation, and action potentials in another SN were unpaired with the shock as a control. The difference between paired and unpaired training is a measure of associative plasticity. Before and after this training, we voltage clamped each SN and measured the outward current during depolarizing pulses. There was a significantly greater decrease in the net outward current in the paired SN than in the unpaired SN. We obtained similar results when we substituted the depolarizing voltage clamp pulse for action potentials during training. We then bathed the ganglion in serotonin as a measure of nonassociative plasticity. The current that was modulated differentially (paired−unpaired) had time and voltage dependencies similar to the current that was modulated by serotonin (Is). These results suggest that an associative form of plasticity, activity-dependent presynaptic facilitation underlying conditioning, involves enhanced modulation of the same ionic current as a nonassociative form, normal presynaptic facilitation underlying sensitization.
Collapse
Affiliation(s)
- Robert D Hawkins
- Department of Neuroscience, Columbia University, New York, New York 10032, USA.,Division of Systems Neuroscience, New York State Psychiatric Institute, New York, New York 10032, USA
| | - Eric R Kandel
- Department of Neuroscience, Columbia University, New York, New York 10032, USA.,Division of Systems Neuroscience, New York State Psychiatric Institute, New York, New York 10032, USA.,Howard Hughes Medical Institute, New York, New York 10032, USA
| |
Collapse
|
6
|
Zhong LY, Fan XR, Shi ZJ, Fan ZC, Luo J, Lin N, Liu YC, Wu L, Zeng XR, Cao JM, Wei Y. Hyperpolarization-Activated Cyclic Nucleotide-Gated Ion (HCN) Channels Regulate PC12 Cell Differentiation Toward Sympathetic Neuron. Front Cell Neurosci 2019; 13:415. [PMID: 31616252 PMCID: PMC6763607 DOI: 10.3389/fncel.2019.00415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 08/28/2019] [Indexed: 12/15/2022] Open
Abstract
Hyperpolarization-activated cyclic nucleotide-gated ion channels (HCN channels) are widely expressed in the central and peripheral nervous systems and organs, while their functions are not well elucidated especially in the sympathetic nerve. The present study aimed to investigate the roles of HCN channel isoforms in the differentiation of sympathetic neurons using PC12 cell as a model. PC12 cells derived from rat pheochromocytoma were cultured and induced by nerve growth factor (NGF) (25 ng/ml) to differentiate to sympathetic neuron-like cells. Sympathetic directional differentiation of PC12 cells were evaluated by expressions of growth-associated protein 43 (GAP-43) (a growth cone marker), tyrosine hydroxylase (TH) (a sympathetic neuron marker) and neurite outgrowth. Results show that the HCN channel isoforms (HCN1-4) were all expressed in PC12 cells; blocking HCN channels with ivabradine suppressed NGF-induced GAP-43 expression and neurite outgrowth; silencing the expression of HCN2 and HCN4 using silenced using small interfering RNAs (siRNA), rather than HCN1 and HCN3, restrained GAP-43 expression and neurite outgrowth, while overexpression of HCN2 and HCN4 channels with gene transfer promoted GAP-43 expression and neurite outgrowth. Patch clamp experiments show that PC12 cells exhibited resting potentials (RP) of about −65 to −70 mV, and also presented inward HCN channel currents and outward (K+) currents, but no inward voltage-gated Na+ current was induced; NGF did not significantly affect the RP but promoted the establishment of excitability as indicated by the increased ability to depolarize and repolarize in the evoked suspicious action potentials (AP). We conclude that HCN2 and HCN4 channel isoforms, but not HCN1 and HCN3, promote the differentiation of PC12 cells toward sympathetic neurons. NGF potentiates the establishment of excitability during PC12 cell differentiation.
Collapse
Affiliation(s)
- Li-Ying Zhong
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Xin-Rong Fan
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Zhang-Jing Shi
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Zhong-Cai Fan
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Jian Luo
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Na Lin
- Department of Respiratory Medicine, Rongcheng People's Hospital, Rongcheng, China
| | - Ying-Cai Liu
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Lin Wu
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China.,Department of Cardiology, Peking University First Hospital, Beijing, China
| | - Xiao-Rong Zeng
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Ji-Min Cao
- Key Laboratory of Cellular Physiology of Ministry of Education, Department of Physiology, Shanxi Medical University, Taiyuan, China
| | - Yan Wei
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| |
Collapse
|
7
|
The contributions and mechanisms of changes in excitability during simple forms of learning in Aplysia. Neurobiol Learn Mem 2019; 164:107049. [PMID: 31362057 DOI: 10.1016/j.nlm.2019.107049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/17/2019] [Accepted: 07/26/2019] [Indexed: 11/21/2022]
Abstract
Learning and memory have long been thought to involve changes in synaptic connections between neurons. However, in many cases learning-related plasticity also involves changes in the excitability of neurons. These findings have raised questions about the relative importance of these two types of mechanisms to behavioral learning, and also about the extent to which they involve shared or unique molecular mechanisms. We have taken a reductionist approach to these questions by addressing them in a simple model organism, Aplysia californica. Studies of a semi-intact Aplysia siphon withdrawal preparation suggest that classical conditioning involves an increase in the evoked firing of sensory neurons (SNs) as well as facilitation of the monosynaptic PSP to motor neurons (MNs). Furthermore, these two mechanisms may act cooperatively at the cellular level: increased SN firing produces more PSPs, each of which is facilitated, leading to a multiplicative increase in depolarization of the MN and siphon withdrawal. The changes in SN firing and the monosynaptic PSP also share several mechanisms at the molecular level, suggesting that they may both be due in part to a decrease in K+ current that causes an increase in SN excitability as well as an increase in SN spike width and thus increased transmitter release. However, changes in the monosynaptic PSP also involve additional mechanisms that are not shared and may affect different aspects of synaptic transmission as well. Studies of operant conditioning of feeding suggest that it involves similar mechanisms as classical conditioning of siphon withdrawal. In particular, for both types of associative learning adenylyl cyclase appears to serve as a molecular coincidence detector that leads to increased activation of PKA and changes in excitability of key neurons in the neural circuit. Furthermore, in both cases those changes in excitability make an important contribution to the behavioral learning.
Collapse
|
8
|
Perkins MH, Weiss KR, Cropper EC. Persistent effects of cyclic adenosine monophosphate are directly responsible for maintaining a neural network state. Sci Rep 2019; 9:9058. [PMID: 31227744 PMCID: PMC6588548 DOI: 10.1038/s41598-019-45241-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 06/04/2019] [Indexed: 01/25/2023] Open
Abstract
Network states are often determined by modulators that alter the synaptic and cellular properties of the constituent neurons. Frequently neuromodulators act via second messengers, consequently their effects can persist. This persistence at the cellular/molecular level determines the maintenance of the state at the network level. Here we study a feeding network in Aplysia. In this network, persistent modulation supports the maintenance of an ingestive state, biasing the network to generate ingestive motor programs. Neuropeptides that exert cyclic adenosine monophosphate (cAMP) dependent effects play an important role in inducing the ingestive state. Most commonly, modulatory effects exerted through cAMP signaling are persistent as a consequence of PKA activation. This is not the case in the neurons we study. Instead maintenance of the network state depends on the persistence of cAMP itself. Data strongly suggest that this is a consequence of the direct activation of a cyclic nucleotide gated current.
Collapse
Affiliation(s)
- Matthew H Perkins
- Icahn School of Medicine at Mt. Sinai, Department of Neuroscience and Friedman Brain Institute, One Gustave L. Levy Place, Box 1065, New York, NY, 10029, USA.
| | - Klaudiusz R Weiss
- Icahn School of Medicine at Mt. Sinai, Department of Neuroscience and Friedman Brain Institute, One Gustave L. Levy Place, Box 1065, New York, NY, 10029, USA
| | - Elizabeth C Cropper
- Icahn School of Medicine at Mt. Sinai, Department of Neuroscience and Friedman Brain Institute, One Gustave L. Levy Place, Box 1065, New York, NY, 10029, USA
| |
Collapse
|
9
|
Yang Q, Antonov I, Castillejos D, Nagaraj A, Bostwick C, Kohn A, Moroz LL, Hawkins RD. Intermediate-term memory in Aplysia involves neurotrophin signaling, transcription, and DNA methylation. ACTA ACUST UNITED AC 2018; 25:620-628. [PMID: 30442770 PMCID: PMC6239133 DOI: 10.1101/lm.047977.118] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 09/16/2018] [Indexed: 12/14/2022]
Abstract
Long-term but not short-term memory and synaptic plasticity in many brain areas require neurotrophin signaling, transcription, and epigenetic mechanisms including DNA methylation. However, it has been difficult to relate these cellular mechanisms directly to behavior because of the immense complexity of the mammalian brain. To address that problem, we and others have examined numerically simpler systems such as the hermaphroditic marine mollusk Aplysia californica. As a further simplification, we have used a semi-intact preparation of the Aplysia siphon withdrawal reflex in which it is possible to relate cellular plasticity directly to behavioral learning. We find that inhibitors of neurotrophin signaling, transcription, and DNA methylation block sensitization and classical conditioning beginning ∼1 h after the start of training, which is in the time range of an intermediate-term stage of plasticity that combines elements of short- and long-term plasticity and may form a bridge between them. Injection of decitabine (an inhibitor of DNA methylation that may have other actions in these experiments) into an LE sensory neuron blocks the neural correlates of conditioning in the same time range. In addition, we found that both DNA and RNA methylation in the abdominal ganglion are correlated with learning in the same preparations. These results begin to suggest the functions and integration of these different molecular mechanisms during behavioral learning.
Collapse
Affiliation(s)
- Qizong Yang
- Department of Neuroscience, Columbia University, New York, New York 10032, USA
| | - Igor Antonov
- Department of Neuroscience, Columbia University, New York, New York 10032, USA
| | - David Castillejos
- Department of Neuroscience, Columbia University, New York, New York 10032, USA
| | - Anagha Nagaraj
- Department of Neuroscience, Columbia University, New York, New York 10032, USA
| | - Caleb Bostwick
- Whitney Laboratory for Marine Biosciences, University of Florida, Saint Augustine, Florida 32080, USA.,Department of Neuroscience, University of Florida, Gainesville, Florida 32610, USA
| | - Andrea Kohn
- Whitney Laboratory for Marine Biosciences, University of Florida, Saint Augustine, Florida 32080, USA
| | - Leonid L Moroz
- Whitney Laboratory for Marine Biosciences, University of Florida, Saint Augustine, Florida 32080, USA.,Department of Neuroscience, University of Florida, Gainesville, Florida 32610, USA
| | - Robert D Hawkins
- Department of Neuroscience, Columbia University, New York, New York 10032, USA.,Division of Systems Neuroscience, New York State Psychiatric Institute, New York, New York 10032, USA
| |
Collapse
|
10
|
Kawasaki Y, Saito M, Won J, Bae JY, Sato H, Toyoda H, Kuramoto E, Kogo M, Tanaka T, Kaneko T, Oh SB, Bae YC, Kang Y. Inhibition of GluR Current in Microvilli of Sensory Neurons via Na +-Microdomain Coupling Among GluR, HCN Channel, and Na +/K + Pump. Front Cell Neurosci 2018; 12:113. [PMID: 29740287 PMCID: PMC5928758 DOI: 10.3389/fncel.2018.00113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 04/06/2018] [Indexed: 11/13/2022] Open
Abstract
Glutamatergic dendritic EPSPs evoked in cortical pyramidal neurons are depressed by activation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels expressed in dendritic spines. This depression has been attributed to shunting effects of HCN current (Ih) on input resistance or Ih deactivation. Primary sensory neurons in the rat mesencephalic trigeminal nucleus (MTN) have the somata covered by spine-like microvilli that express HCN channels. In rat MTN neurons, we demonstrated that Ih enhancement apparently diminished the glutamate receptor (GluR) current (IGluR) evoked by puff application of glutamate/AMPA and enhanced a transient outward current following IGluR (OT-IGluR). This suggests that some outward current opposes inward IGluR. The IGluR inhibition displayed a U-shaped voltage-dependence with a minimal inhibition around the resting membrane potential, suggesting that simple shunting effects or deactivation of Ih cannot explain the U-shaped voltage-dependence. Confocal imaging of Na+ revealed that GluR activation caused an accumulation of Na+ in the microvilli, which can cause a negative shift of the reversal potential for Ih (Eh). Taken together, it was suggested that IGluR evoked in MTN neurons is opposed by a transient decrease or increase in standing inward or outward Ih, respectively, both of which can be caused by negative shifts of Eh, as consistent with the U-shaped voltage-dependence of the IGluR inhibition and the OT-IGluR generation. An electron-microscopic immunohistochemical study revealed the colocalization of HCN channels and glutamatergic synapses in microvilli of MTN neurons, which would provide a morphological basis for the functional interaction between HCN and GluR channels. Mathematical modeling eliminated the possibilities of the involvements of Ih deactivation and/or shunting effect and supported the negative shift of Eh which causes the U-shaped voltage-dependent inhibition of IGluR.
Collapse
Affiliation(s)
- Yasuhiro Kawasaki
- Department of Neuroscience and Oral Physiology, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Mitsuru Saito
- Department of Neuroscience and Oral Physiology, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Jonghwa Won
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Dental Research Institute and Department of Neurobiology and Physiology, School of Dentistry, Seoul National University, Seoul, South Korea
| | - Jin Young Bae
- Department of Oral Anatomy, School of Dentistry, Kyungpook National University, Daegu, South Korea
| | - Hajime Sato
- Department of Neuroscience and Oral Physiology, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Hiroki Toyoda
- Department of Neuroscience and Oral Physiology, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Eriko Kuramoto
- Department of Morphological Brain Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Mikihiko Kogo
- Department of Neuroscience and Oral Physiology, Graduate School of Dentistry, Osaka University, Osaka, Japan
| | - Takuma Tanaka
- Department of Computational Intelligence and Systems Science, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Takeshi Kaneko
- Department of Morphological Brain Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Seog Bae Oh
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Dental Research Institute and Department of Neurobiology and Physiology, School of Dentistry, Seoul National University, Seoul, South Korea
| | - Yong Chul Bae
- Department of Oral Anatomy, School of Dentistry, Kyungpook National University, Daegu, South Korea
| | - Youngnam Kang
- Department of Neuroscience and Oral Physiology, Graduate School of Dentistry, Osaka University, Osaka, Japan
| |
Collapse
|
11
|
Liu Q, Wu C, Huang S, Wu Q, Zhou T, Liu X, Liu X, Hu X, Li L. Decreased hyperpolarization-activated cyclic nucleotide-gated channels are involved in bladder dysfunction associated with spinal cord injury. Int J Mol Med 2018; 41:2609-2618. [PMID: 29436607 PMCID: PMC5846662 DOI: 10.3892/ijmm.2018.3489] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 02/08/2018] [Indexed: 12/12/2022] Open
Abstract
Spinal cord injury (SCI) leads to bereft voluntary control of bladder, but the possible role of spontaneous excited system in bladder of SCI patients is poorly understood. Hyper polarization-activated cyclic nucleotide-gated (HCN) channels are deemed to regulate the spontaneous contraction of bladder, our study explored the functional role of HCN channels in SCI induced neurogenic bladder. Sixty female Sprague-Dawley rats were randomized into control, sham and SCI groups. Rat models subjected to SCI at S2 levels were successfully established and were assessed using hematoxylin and eosin staining and cystometry. In SCI rats, the mRNA and protein expression levels of HCN channels and the Ih density were significantly reduced, and expression levels of several bladder HCN1 channel regulatory proteins were also significantly changed. The effects of 50 µM forskolin and 50 µM 8-bromoadenosine 3′,5′-cyclic monophosphate on [Ca2+]i of isolated bladder interstitial cells of Cajal-like cells were significantly decreased in SCI rats. The spontaneous contractions in detrusor strips from SCI rats were significantly weakened. Furthermore, detrusor strips from SCI rats exhibited decreased tolerance to two doses of ZD7288 (10 and 50 µM). Taken together, our results indicate that the decreased bladder HCN channel expression and function induced by altered regulatory proteins are involved in the pathological process of SCI induced neurogenic bladder, which present HCN channels as valid therapeutic targets for treating this disease.
Collapse
Affiliation(s)
- Qian Liu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Chao Wu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Shengquan Huang
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Qingjian Wu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Tao Zhou
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Xiaobing Liu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Xin Liu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Xiaoyan Hu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Longkun Li
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| |
Collapse
|
12
|
Sartiani L, Mannaioni G, Masi A, Novella Romanelli M, Cerbai E. The Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: from Biophysics to Pharmacology of a Unique Family of Ion Channels. Pharmacol Rev 2017; 69:354-395. [PMID: 28878030 DOI: 10.1124/pr.117.014035] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/07/2017] [Indexed: 12/22/2022] Open
Abstract
Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels are important members of the voltage-gated pore loop channels family. They show unique features: they open at hyperpolarizing potential, carry a mixed Na/K current, and are regulated by cyclic nucleotides. Four different isoforms have been cloned (HCN1-4) that can assemble to form homo- or heterotetramers, characterized by different biophysical properties. These proteins are widely distributed throughout the body and involved in different physiologic processes, the most important being the generation of spontaneous electrical activity in the heart and the regulation of synaptic transmission in the brain. Their role in heart rate, neuronal pacemaking, dendritic integration, learning and memory, and visual and pain perceptions has been extensively studied; these channels have been found also in some peripheral tissues, where their functions still need to be fully elucidated. Genetic defects and altered expression of HCN channels are linked to several pathologies, which makes these proteins attractive targets for translational research; at the moment only one drug (ivabradine), which specifically blocks the hyperpolarization-activated current, is clinically available. This review discusses current knowledge about HCN channels, starting from their biophysical properties, origin, and developmental features, to (patho)physiologic role in different tissues and pharmacological modulation, ending with their present and future relevance as drug targets.
Collapse
Affiliation(s)
- Laura Sartiani
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Guido Mannaioni
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Alessio Masi
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Maria Novella Romanelli
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Elisabetta Cerbai
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| |
Collapse
|
13
|
Serfőző Z, Nacsa K, Veréb Z, Battonyai I, Hegedűs C, Balogh C, Elekes K. Nitric oxide-coupled signaling in odor elicited molecular events in the olfactory center of the terrestrial snail, Helix pomatia. Cell Signal 2016; 30:67-81. [PMID: 27884734 DOI: 10.1016/j.cellsig.2016.11.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/15/2016] [Accepted: 11/18/2016] [Indexed: 12/22/2022]
Abstract
Olfaction, a chemosensory modality, plays a pivotal role in the orientation and behavior of invertebrates. The central olfactory processing unit in terrestrial stylomatophoran snails is the procerebrum, which contains NO synthesizing interneurons, whose oscillatory currents are believed to be the base of odor evoked memory formation. Nevertheless, in this model the up- and downstream events of molecular cascades that trigger and follow NO release, respectively, have not been studied. Immunocytochemistry and flow cytometry studies performed on procerebral neural perikarya isolated from the snail Helix pomatia revealed cell populations with discrete DAF-2 fluorescence, indicating the release of different amounts of NO. Glutamate increased the intensity of DAF-2 fluorescence, and the number of DAF-2 positive non-bursting interneurons, through a mechanism likely to involve an NMDA-like receptor. Similarly to glutamate, NO activation induced an increase in intracellular cGMP levels through activation of soluble guanylyl cyclase. Immunohistochemical localization of proteins possessing the phosphorylated target sequence of AGC family kinases (RXXS/T-P), among them protein kinase A (RRXS/T-P), showed striking similarities to the distribution of NOS/cGMP. Activators of cyclic nucleotide synthesis increased the AGC-kinase-dependent phosphorylation of discrete proteins with 28, 45, and 55kDamw. Importantly, exposure of snails to an attractive odorant induced hyperphosphorylation of the 28kDa protein, and increased levels of cGMP synthesis. Protein S-nitrosylation and intercellular activation of protein kinase G were also suggested as alternative components of NO signaling in the snail procerebrum. The present results from Helix pomatia indicate an important role for procerebrum NO/cGMP/PKA signaling pathways in the regulation of olfactory (food-finding) behavior.
Collapse
Affiliation(s)
- Zoltán Serfőző
- MTA Centre for Ecological Research, Balaton Limnological Institute, Tihany, Hungary.
| | - Kálmán Nacsa
- MTA Centre for Ecological Research, Balaton Limnological Institute, Tihany, Hungary
| | - Zoltán Veréb
- Institute of Biochemistry and Molecular Biology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary
| | - Izabella Battonyai
- MTA Centre for Ecological Research, Balaton Limnological Institute, Tihany, Hungary
| | - Csaba Hegedűs
- Institute of Medical Chemistry, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary
| | - Csilla Balogh
- MTA Centre for Ecological Research, Balaton Limnological Institute, Tihany, Hungary
| | - Károly Elekes
- MTA Centre for Ecological Research, Balaton Limnological Institute, Tihany, Hungary
| |
Collapse
|