Figure 5.

An antibody to the ligand-binding domain of LRP increases [Ca²⁺]_i, but an antibody to an intracellular domain of LRP does not. This figure illustrates two experiments using rabbit polyclonal antibodies directed against LRP. In the top trace (●), R777 was added, which recognizes the ligand-binding domain of LRP. The addition of R777 increases [Ca²⁺]_i in a neuron-specific manner. In the bottom trace (■), the addition of R704, which recognizes an intracellular domain of LRP, is unable to elicit an increase in [Ca²⁺]_i. However, the subsequent addition of α₂M* is able to generate a calcium response in these cells. Each trace is the average of seven cells in a field.