Review Article

Role of Ryanodine Receptor Subtypes in Initiation and Formation of Calcium Sparks in Arterial Smooth Muscle: Comparison with Striated Muscle

Figure 1

Calcium spark in a rat tibial artery smooth muscle cell. (a) Series of 8 consecutive laser scanning confocal images (17 milliseconds apart) illustrating a calcium spark. The calcium spark area is marked by a square and the peak of the calcium spark is indicated by arrows (b). The myocyte was loaded with the indicator dye fluo-3. Two-dimensional (2D) images were obtained using a Nipkow spinning disk confocal microscope (Perkin Elmer, UltraView LCI). (b) Three-dimensional plot of fluorescence intensity of the cell shown in (a) at 68 milliseconds. The calcium spark occurred in close proximity to the plasma membrane. (c) Time course of the calcium spark in the marked area. The amplitude is expressed as . is the fluorescence intensity in the marked area where the spark appeared. is fluorescence intensity of the same cell area in the absence of calcium spark.
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