FIGURE 8.

Sarcomere length by Fourier analysis. (A) Sarcomeres in myocytes grown in an EHT were visualized by scanning confocal microscopy after fluorescence staining of titin. (B) An intensity profile is plotted along a straight line shown by the square bracket. (C) A strong peak (∼0.525 1/μm) shown in the frequency domain of the intensity profile (0.19 μm) indicates the sarcomere periodicity and yields a value of the sarcomere spacing. (D) Comparison of nonstretched (0%) and stretched (1%) sarcomere were visualized. The fluorescence peaks counted from the edge of the image to the vertical yellow line were 20 and 18–19 in nonstretched and in stretched sample, respectively. (Bar = 4 μm).