Figure 7
Dose-response relationships for the functional-HOTSM with focus on variation in c. Constant c is varied in five steps from 10-4 (—) to 104 (-..-..-..) by a factor 100. Other parameters were varied as indicated. The third plateau at high concentrations, 1/[1+1/(L·a·b·d)], is independent of parameter c. Parameter c determines the width of the second plateau, thus for decreasing values of c the width broadens. The third plateau, TP, is above the first and second plateaus in panel A. In panel B, TP is below the first plateau but above the second plateau, eliciting reverse bell-shaped curves for certain parameter values. Fitting a four parameter Hill equation to the steepest dose-response curve 1 in panel A yields a Hill coefficient, nH, equal to 1.99, while a fit to the dose-response curve 2 in panel A give nH = 0.68, for c = 100.