Figure 6.

Y₁ receptors tonically suppress TH expression in the adrenal medulla. A, RT-PCR of Y receptor expression in the adrenal medulla and CNS (positive control) of wild-type mice. Amplicons indicate the presence of mRNAs encoding Y₁, Y₂, Y₄, and Y₅ receptors and NPY in the adrenal medulla (Ad. med; results are tabulated on the right). The negative control (RT−) contained NPY primers but lacked reverse transcriptase. B, TH-IR in adrenal sections from saline-injected control mice or after injection with Y₁, Y₂, or Y₅ antagonists. Group data shows that BIBP 3226 (a Y₁ antagonist) significantly increased the basal level of TH-IR. Group data shows mean ± SEM, n = 3 independent experiments (7–10 sections from each animal). C, TH-IR in adrenal sections from mice exposed to the FST and injected with either saline or Y₁, Y₂, or Y₅ antagonists. Group data shows that only BIBP 3226 significantly increased the level of TH-IR. Group data shows mean ± SEM, n = 3 independent experiments (7–10 sections from each animal). Scale bars, 100 μm. *p < 0.05.