Related Experiment Videos
Electromechanical dissociation in the human skeletal muscle
1Department of Neurology, Electromyography Laboratory, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA.
Abstract:
It is not clear whether electromechanical dissociation can be a significant cause of clinical weakness in the human skeletal muscle. One type of muscle disorder suggests that this may occur. The condition results from the use of large doses of corticosteroids in conjunction with a neuromuscular blocking agent. In this situation, the thick myosin filaments of the sarcomere are preferentially disrupted. This may selectively compromise the contractile properties of the skeletal muscle fiber, without necessarily implicating the integrity of the muscle membrane. Thus, a muscle fiber might still be able to depolarize electrically, producing a membrane action potential, without necessarily generating an appropriate mechanical response.