Biphasic regulation in ligand-receptor interactions.

A model is examined in which an excess of activator may inhibit the response in a ligand-receptor interaction. The equation accounts for biphasic responses in which an effector stimulates the response at low concentrations and then inhibits the response at higher concentrations, towards a limit that can be higher, identical or lower than the initial value. Reciprocal features could be observed according to the values of the involved parameters. A maximum 7 dimensions can be found in the space of the parameters of the equation which is of the simple form: v = (A + B + C). Sn/(H + Sn).