title: Detection of calcium sparks in intact and permeabilized skeletal muscle fibers.
abstract: Ca(2+) sparks are the elementary units of Ca(2+) signaling in striated muscle fibers that appear as highly localized Ca(2+) release events through ryanodine receptor (RyR) Ca(2+) release channels in the sarcoplasmic reticulum (SR). While these events are commonly observed in resting cardiac myocytes, they are rarely seen in resting skeletal muscle fibers. Since Ca(2+) spark analysis can provide extensive data on the Ca(2+) handling characteritsics of normal and diseased striated muscle, there has been interest in developing methods for observing Ca(2+) sparks in skeletal muscle. Previously, we discovered that stress generated by osmotic pressure changes induces a robust Ca(2+) spark response confined in close spatial proximity to the sarcolemmal membrane in wild-type intact mammalian muscles. Our studies showed these peripheral Ca(2+) sparks (PCS) were altered in dystrophic or aged skeletal muscles. Other methods to induce Ca(2+) sparks include permeabilization of the sarcolemmal membrane with detergents, such as saponin. In this chapter, we will discuss the methods for isolation of muscle fibers, the techniques for inducing Ca(2+) sparks in these isolated fibers, and provide guidance on the analysis of data from these experiments.
authors: Department of Physiology and Biophysics, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ, USA. noah.weisleder@umdnj.edu
authors: Noah
authors: N
authors: Weisleder
authors: Jingsong
authors: J
authors: Zhou
authors: Jianjie
authors: J
authors: Ma
mesh_terms: D000818:Animals; D002118:Calcium / Q000032:analysis* / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects; D002469:Cell Separation / Q000379:methods; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D009997:Osmotic Pressure / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012503:Saponins / Q000494:pharmacology
chemical_list: D012503:Saponins; D002118:Calcium