Fig. 4.

Age extenuates the effects of pressure on endothelial Ca²⁺ signaling. Summary data illustrating the pressure dependence of the Ca²⁺ response (peak ΔF/F₀) of endothelial cells activated by ACh in young (a; 948 cells from 8 animals) and aged rats (b; 616 cells from 6 animals). Cellular responses have been normalized to the average response occurring at 60 mm Hg. The responses are colored according to the density of plotted data points, and distributions obtained by kernel density estimation are shown for each pressure (see online version for colors). c Summary data illustrating inhibition of endothelial Ca²⁺ signaling in young and aged rats. Ca²⁺ response inhibition (means ± SEM) are defined as the difference between the response at the indicated pressure and control values. * p < 0.05.