FIGURE 3

Effects of CaSR agonists on [Ca²⁺]_i levels in HEK 293 transfected with rat CaSR. The ability of CaSR agonists to activate rat CaSR was assessed by monitoring [Ca²⁺]_i levels following the addition of gadolinium (A), neomycin (B), or magnesium (C) to the extracellular fluid using fura 2-loaded cells, as described in the Methods section. Additions of gadolinium, neomycin, and magnesium at the indicated concentrations caused similar increments in [Ca²⁺]_i levels in HEK 293 cells transfected with rat CaSR. Results are representative of four to six separate experiments per compound.