THE EFFECT OF ELECTRICAL-STIMULATION ON SKELETAL-MUSCLE PROPERTIES

Skeletal muscle fibres are versatile entities, capable of changing their phenotype in response to altered functional demands. A large body of information in support of this has been derived from experiments using low frequency chronic electrical stimulation of mammalian fast twitch muscles. This type of activity, which is characteristic of that imposed upon a slow twitch muscle induces a conversion of fast muscle fibres towards slow ones. The changes induced by low frequency electrical stimulation affect all functional components of the muscle fibre, i.e., the Ca2+, handling system, energy metabolism and the contractile apparatus. The molecular mechanisms and the signals that trigger the transformation process are as yet obscure and are being explored.