Figure 3. Transverse cardiac sections.

A series of typical transverse sections taken at right angles to the principal cardiac axis at one spatial slice obtained from a normal male WKY weighing 309 g and aged 12 weeks (A) and a male SHR weighing 319 g and aged 12 weeks (B). Intrinsic heart rates were 295 ± 4 beats min⁻¹ for the WKY rat and 287 ± 7 beats min⁻¹ for the SHR. Each image is the average of two signals obtained at corresponding points in the cardiac cycle following the R wave. The time indicated in the upper left-hand corner of each panel is the delay after the trigger, taken from the R wave, at which the signal was acquired. LV and RV indicate the left and right ventricles, respectively. The nominal in-plane resolutions for the WKY and SHR were, respectively, 350 and 390 μm and slice thicknesses were 1.44 and 1.37 mm. For display, the images have been zero-padded from a matrix of 128 to 256 pixels square. The effective repeat time was approximately 400 ms. The scale bars indicate 5 mm.