Figure 3.

Effects of RAR agonist and RAR antagonist on RA-induced translocation of M6P/IGF2R and cathepsin B. Cultured neonatal-rat cardiac fibroblasts were treated either with 0.25 μM RA and 3 μM AGN193109 (RAR antagonist; A and B) or with 1 μM NNTPB alone (RAR agonist; C and D) for 3 h. Distribution of M6P/IGF2R (A and C) and cathepsin B (B and D) was detected by immunofluorescence with anti-M6P/IGF2R antibodies and anti-cathepsin B antibodies, respectively. The RAR antagonist failed to block the effect of RA, and the RAR agonist did not mimic the effect of RA shown in Figs. 1 and 2. (Bars = 20 μm.)