Dynamic Changes in Sarcoplasmic Reticulum Structure in Ventricular Myocytes
Figure 3
Motile corbular SR boutons in neonatal and adult ventricular myocytes. (a) Time-lapse confocal images of a neonatal ventricular myocytes expressing tRFP-SR. Images shown were obtained 0, 150, and 300 seconds after the initiation of the experiment. Motile corbular SR boutons are labeled with colored circles. (b) Plot of the velocity of corbular SR boutons i and ii as a function of time. (c) Time-course of corbular SR bouton motility in a representative adult ventricular myocyte expressing tRFP-SR. The insets in the lower right corner of each image show an expansion of the region in the cell marked by the red box. (d) Plot of velocity of this corbular SR bouton as a function of time. (e) Bar plot of the mean velocity of corbular SR boutons in neonatal and adult ventricular myocytes (*). (f) Histogram of the total distance traveled over a period of 300 seconds of 79 corbular SR boutons in adult and neonatal ventricular myocytes. (g) Histogram of the step distance traveled by corbular SR boutons. The inset shows an expanded view of the region of the histogram from 1.8 to 4.2 μm.
