New perspectives of studying gastrointestinal muscle function

Figure 1 A: Relationship between left ventricular volume and pressure during diastole and systole. The arrows indicate the four phases of the volume-pressure diagram during the normal cardiac cycle; B: Ventricular function curves expressing the Frank-Starling mechanism of the heart, i.e. the intrinsic ability of the heart to adapt to changing volumes of inflowing blood; C: Schematic plot of shortening velocity vs force. The relationship has in muscle tissues shown to be hyperbolic. The y-intercept is called Vmax which reflects the maximum crossbridge turnover rate. The x-intercept is the peak isometric force, Fmax, which is determined by the number of attached crossbridges (Modified from Guyton and Hall 2002 and others).