Fig. 4.

Effects of bile acids on CCK1R expressed in an elevated membrane cholesterol environment. A and B: CCK competition-binding curves at the CCK1R expressed in SRD15-CCK1R cells possessing increased membrane cholesterol in the absence (control) and presence of 1 mM TUDC and 0.5 mM TCDC. Values (means ± SE of ≥3 independent experiments performed in duplicate) represent percentage of saturable binding for each curve (A) and percentage of control (B). C: curves for concentration-dependent intracellular calcium responses to CCK in SRD15-CCK1R cells after treatments described in A and B. Values (means ± SE of ≥5 independent experiments performed in duplicate) were normalized to maximal response to 0.1 mM ATP.