Figure 5. Structure-activity relationship study on the agonistic activity of Brompheniramine on the pMV-absorption.

(A) Chemical structures of structurally- or functionally-related compounds of Brompheniramine are shown. Refer to Supplementary Figure 4 for their names and pharmacological uses. (B) 2C T cells were treated with compounds shown in (A) at titrated concentrations and cultured with the QL9-loaded pMVs followed by mAb staining for B7-1. MFIs of the B7-1 staining relative to that of 2C T cells treated with DMSO alone were plotted. Experiments were performed in duplicate and standard deviations of duplicate samples were all within 10% of the averages. Shown is one of three representative experiments. (C) ED₅₀s of the compounds were calculated from the experiments described in (B) and plotted against Kis of the compounds for 5-HT transporter. Note: Ki values used in this plot were adopted from PDSP Ki data base (http://pdsp.med.unc.edu/pdsp.php). To ensure data consistency, only the Ki values obtained using rat frontal cortex as the source of 5-HT transporter and [³H]-5-HT as the hot ligand were used [45].