Review
Central Role of Subthreshold Currents in Myotonia
Sabrina Metzger,
Chris Dupont,
Andrew A. Voss PhD,
Mark M. Rich MD, PhD,
Sabrina Metzger
Department of Neuroscience, Cell Biology, and Physiology, Wright State University, Dayton, OH
Search for more papers by this authorChris Dupont
Department of Neuroscience, Cell Biology, and Physiology, Wright State University, Dayton, OH
Search for more papers by this authorAndrew A. Voss PhD
Department of Biology, Wright State University, Dayton, OH
Search for more papers by this authorCorresponding Author
Mark M. Rich MD, PhD
Department of Neuroscience, Cell Biology, and Physiology, Wright State University, Dayton, OH
Address correspondence to
Dr Rich, Department of Neuroscience, Cell Biology, and Physiology, Wright State University, 3640 Colonel Glenn Hwy, Dayton, OH 45435.
E-mail: [email protected]
Search for more papers by this authorSabrina Metzger,
Chris Dupont,
Andrew A. Voss PhD,
Mark M. Rich MD, PhD,
Sabrina Metzger
Department of Neuroscience, Cell Biology, and Physiology, Wright State University, Dayton, OH
Search for more papers by this authorChris Dupont
Department of Neuroscience, Cell Biology, and Physiology, Wright State University, Dayton, OH
Search for more papers by this authorAndrew A. Voss PhD
Department of Biology, Wright State University, Dayton, OH
Search for more papers by this authorCorresponding Author
Mark M. Rich MD, PhD
Department of Neuroscience, Cell Biology, and Physiology, Wright State University, Dayton, OH
Address correspondence to
Dr Rich, Department of Neuroscience, Cell Biology, and Physiology, Wright State University, 3640 Colonel Glenn Hwy, Dayton, OH 45435.
E-mail: [email protected]
Search for more papers by this authorAbstract
It is generally thought that muscle excitability is almost exclusively controlled by currents responsible for generation of action potentials. We propose that smaller ion channel currents that contribute to setting the resting potential and to subthreshold fluctuations in membrane potential can also modulate excitability in important ways. These channels open at voltages more negative than the action potential threshold and are thus termed subthreshold currents. As subthreshold currents are orders of magnitude smaller than the currents responsible for the action potential, they are hard to identify and easily overlooked. Discovery of their importance in regulation of excitability opens new avenues for improved therapy for muscle channelopathies and diseases of the neuromuscular junction. ANN NEUROL 2020;87:175–183
Potential Conflicts of Interest
Nothing to report.
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