Setting Up Osmotic-stress Perfusion System and Solution Preparation
2:00
Preparing Intact Single Flexor Digitorum Brevis (FDB) Muscle Fibers from Mouse
5:12
Fluo-4 AM Dye Loading and Ca2+ Imaging (Sparks Measurement)
7:39
Data Analysis
8:14
Results: Ca2+ Sparks in Young, Aged, and Diseased Mice
10:28
Conclusion
Described here is a method to directly measure calcium sparks, the elementary units of Ca2+ release from sarcoplasmic reticulum in intact skeletal muscle fibers. This method utilizes osmotic-stress-mediated triggering of Ca2+ release from ryanodine receptor in isolated muscle fibers. The dynamics and homeostatic capacity of intracellular Ca2+ signaling can be employed to assess muscle function in health and disease.