Cardiac Muscle Function: Results from Skinned Fiber Preparations

During the last decade cardiac muscle preparations with disrupted surface membranes (skinned fibers) have been used with increasing frequency to study cardiac muscle function. Removal of the surface membrane as an effective permeability barrier allows the experimenter to control the ionic conditions surrounding the contractile proteins and intracellular organelles. Several different techniques are used to disrupt or remove the surface membranes of cardiac muscle. The resulting preparations differ significantly in size, in the extent of membrane removal, and in some cases in their physiological response. Skinned cardiac fibers have been used to study the physiological properties of the contractile proteins and sarcoplasmic reticulum. The influences of disease and pharmacologic agents on normal muscle function have also been investigated.