Next Article in Journal
Cross-Linked Self-Assembling Peptides and Their Post-Assembly Functionalization via One-Pot and In Situ Gelation System
Next Article in Special Issue
Nicotinamide Phosphoribosyltransferase (Nampt)/Nicotinamide Adenine Dinucleotide (NAD) Axis Suppresses Atrial Fibrillation by Modulating the Calcium Handling Pathway
Previous Article in Journal
Oxidative Stress and Thrombosis during Aging: The Roles of Oxidative Stress in RBCs in Venous Thrombosis
Previous Article in Special Issue
Inhibitory Effective Perturbations of Cilobradine (DK-AH269), A Blocker of HCN Channels, on the Amplitude and Gating of Both Hyperpolarization-Activated Cation and Delayed-Rectifier Potassium Currents
Open AccessArticle

Effectiveness in the Block by Honokiol, a Dimerized Allylphenol from Magnolia Officinalis, of Hyperpolarization-Activated Cation Current and Delayed-Rectifier K+ Current

1
Institute of Neuroscience, National Chengchi University, Taipei 11605, Taiwan
2
Center of Neuropsychiatric Research, National Health Research Institutes, Miaoli County 35053, Taiwan
3
Department of Pharmacology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
4
Department of Physiology, National Cheng Kung University Medical College, Tainan 70101, Taiwan
5
Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan 70101, Taiwan
6
Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40402, Taiwan
*
Author to whom correspondence should be addressed.
Int. J. Mol. Sci. 2020, 21(12), 4260; https://doi.org/10.3390/ijms21124260
Received: 13 May 2020 / Revised: 3 June 2020 / Accepted: 9 June 2020 / Published: 15 June 2020
(This article belongs to the Special Issue Electrophysiology)
Background: Honokiol (HNK), a dimer of allylphenol obtained from the bark of Magnolia officinalis was demonstrated to exert an array of biological actions in different excitable cell types. However, whether or how this compound can lead to any perturbations on surface–membrane ionic currents remains largely unknown. Methods: We used the patch clamp method and found that addition of HNK effectively depressed the density of macroscopic hyperpolarization-activated cation currents (Ih) in pituitary GH3 cells in a concentration-, time- and voltage-dependent manner. By the use of a two-step voltage protocol, the presence of HNK (10 μM) shifted the steady-state activation curve of Ih density along the voltage axis to a more negative potential by approximately 11 mV, together with no noteworthy modification in the gating charge of the current. Results: The voltage-dependent hysteresis of Ih density elicited by long-lasting triangular ramp pulse was attenuated by the presence of HNK. The HNK addition also diminished the magnitude of deactivating Ih density elicited by ramp-up depolarization with varying durations. The effective half-maximal concentration (IC50) value needed to inhibit the density of Ih or delayed rectifier K+ current identified in GH3 cells was estimated to be 2.1 or 6.8 μM, respectively. In cell-attached current recordings, HNK decreased the frequency of spontaneous action currents. In Rolf B1.T olfactory sensory neurons, HNK was also observed to decrease Ih density in a concentration-dependent manner. Conclusions: The present study highlights the evidence revealing that HNK has the propensity to perturb these ionic currents and that the hyperpolarization-activated cyclic nucleotide-gated (HCN) channel is proposed to be a potential target for the in vivo actions of HNK and its structurally similar compounds. View Full-Text
Keywords: honokiol; hyperpolarization-activated cation current; current kinetics; pituitary cell; olfactory neuron honokiol; hyperpolarization-activated cation current; current kinetics; pituitary cell; olfactory neuron
Show Figures

Figure 1

MDPI and ACS Style

Chan, M.-H.; Chen, H.-H.; Lo, Y.-C.; Wu, S.-N. Effectiveness in the Block by Honokiol, a Dimerized Allylphenol from Magnolia Officinalis, of Hyperpolarization-Activated Cation Current and Delayed-Rectifier K+ Current. Int. J. Mol. Sci. 2020, 21, 4260. https://doi.org/10.3390/ijms21124260

AMA Style

Chan M-H, Chen H-H, Lo Y-C, Wu S-N. Effectiveness in the Block by Honokiol, a Dimerized Allylphenol from Magnolia Officinalis, of Hyperpolarization-Activated Cation Current and Delayed-Rectifier K+ Current. International Journal of Molecular Sciences. 2020; 21(12):4260. https://doi.org/10.3390/ijms21124260

Chicago/Turabian Style

Chan, Ming-Huan; Chen, Hwei-Hsien; Lo, Yi-Ching; Wu, Sheng-Nan. 2020. "Effectiveness in the Block by Honokiol, a Dimerized Allylphenol from Magnolia Officinalis, of Hyperpolarization-Activated Cation Current and Delayed-Rectifier K+ Current" Int. J. Mol. Sci. 21, no. 12: 4260. https://doi.org/10.3390/ijms21124260

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop