Fig. 5.

Steady-state RBF autoregulation. A: MAP-RBF relationship before and 2 min after a step increase in MAP in +/+ (■, n = 9) and m/m (□, n = 7). The step increase in pressure was similar between groups (see Fig. 2E). B: autoregulatory index, an indicator of the efficiency of steady-state autoregulation, was not significantly different between groups. C: scatter plot of resting MAP vs. autoregulatory index in β-ENaC mice. Although resting MAP influences the autoregulatory index, there is no difference in this relationship between β-ENaC +/+ and m/m mice. D: contribution of myogenic and TGF mechanisms to autoregulation. The reduced contribution of the myogenic mechanism in β-ENaC m/m mice tends to be compensated by enhanced TGF. Data are means ± SE. P values for analysis with t-test are provided. *Significantly different from +/+ control animals, P < 0.05.