Using a new technique to evaluate working muscles in mice, researchers have uncovered physiological mechanisms that could lead to new strategies for combating metabolism-related disorders like muscle wasting and obesity. The study appears in The Journal of General Physiology.
ATP-sensitive potassium (KATP) channels, which link membrane excitability to cell metabolism, are abundant in skeletal muscle and play an important role in regulating muscle function and energy consumption. However, it is not clear how KATP activation affects muscles under physiological conditions and how this translates to energy use.
Researchers from the University of Iowa Carver College of Medicine developed a technique to evaluate muscle function in the tibialis anterior leg muscle of living mice. They found that, during low-level exercise, which triggered the opening of KATP channels, muscles with disrupted KATP function had higher peak force, calcium release, and heat production— which is associated with increased energy consumption— than muscles with normal KATP function.
The results show how KATP channels control energy use even during mundane, low-intensity activity. Modulating KATP channel activity could therefore provide a new strategy to combat metabolic disorders like muscle wasting and cachexia, when the goal is to conserve energy, or obesity, when increasing energy consumption is desired.
More information: Zhu, Z., et al. 2014. J. Gen. Physiol. DOI: 10.1085/jgp.201311063