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Updated: Mar 21, 2026
10:28
A Semi-High-Throughput Adaptation of the NADH-Coupled ATPase Assay for Screening Small Molecule Inhibitors
Published on: August 17, 2019
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Na,K-ATPase regulation in skeletal muscle
Sergej Pirkmajer1, Alexander V Chibalin2
1Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia; and.
Summary
Skeletal muscle
Area of Science:
- Physiology
- Molecular Biology
- Biochemistry
Background:
- Skeletal muscle possesses a large and dynamic pool of Na,K-ATPase (NKA).
- NKA activity is crucial for maintaining muscle function and whole-body homeostasis.
- NKA operates below maximal capacity at rest but is activated by increased ion transport demands.
Purpose of the Study:
- To review the molecular mechanisms regulating NKA in skeletal muscle.
- To highlight stimuli that link NKA regulation with skeletal muscle energy metabolism.
- To discuss novel regulatory roles in NKA function.
Main Methods:
- Review of existing literature on NKA regulation in skeletal muscle.
- Focus on extrinsic and local stimuli impacting NKA.
- Emphasis on molecular mechanisms and signaling pathways.
Main Results:
- NKA is regulated by extrinsic (hormones, nerve factors) and local (contractions, energy status) stimuli.
- Regulation occurs acutely (activity, distribution) and chronically (gene expression).
- Insulin and AMP-activated protein kinase link NKA regulation to energy metabolism.
Conclusions:
- Coordinated regulation of NKA is essential for skeletal muscle and systemic homeostasis.
- Molecular mechanisms involve acute and chronic adaptations.
- Emerging roles of glutathionylation, nitric oxide, and extracellular K+ are significant.
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