Figure 3.

Serotonin uptake rates and surface SERT binding in rhesus PBCs. (a) Maximal uptake rates were calculated using nonlinear curve fitting for data from individual animals. Mean maximal uptake rates with respect to genotype are shown in the inset. One-way analysis of variance indicated that maximal uptake rates vary with respect to rh5-HTTLPR genotype (F(2,12)=5.9; P<0.05). A priori comparisons of uptake rates using one-tailed Student's t-tests showed significant decreases associated with the ‘S' allele (t=3.4, df=7, P<0.01 L/L vs S/L and t=3.0, df=10, P<0.01 L/L vs S/S). (b) Binding of (¹²⁵I)RTI-55 to intact PBCs was used to determine the levels of SERT located at the plasma membrane. Maximal binding was calculated for data from individual animals by nonlinear curve fitting using one-site saturation isotherms. Mean maximal binding as a function of genotype is shown in the inset. There was a trend toward decreased SERT binding associated with the ‘S' allele (F(2,12)=2.5; P<0.12). Data are means±s.e.m.s with N=6 for L/L, N=3 for S/L, and N=6 for S/S. ^**P<0.01 vs the L/L genotype.