Skip to main content
. 2017 Jun 14;13(8):1404–1419. doi: 10.1080/15548627.2017.1328347

Figure 1.

Figure 1.

Dopamine 5 receptor is involved in CAB-mediated suppression of pituitary tumor cell growth. (A) Cell viability upon CAB treatment in MMQ cells. At 50 μM and 100 μM, 48-h CAB treatment reduced the viable cell count by 41.3% (p < 0.01) and 81.9% (p < 0.001), respectively. (B) DRD2-specific agonist quinpirole treatment at 48 h slightly reduced MMQ cell viability by 20% to 25% (p < 0.001). (C) DRD5 agonist SKF83959 treatment at 5, 25, and 50 μM reduced MMQ cell viability by 35%, 44%, and 56%, respectively (p < 0.001). (D) Cell viability upon CAB treatment in GH3 cells. At 50 μM and 100 μM, 48-h CAB treatment reduced the viable cell count by 35% (p < 0.05) and 58% (p < 0.01), respectively. (E) DRD2 agonist quinpirole treatment at 48 h had no effect on GH3 cell viability. (F) DRD5 agonist SKF83959 treatment at 5, 25, and 50 μM reduced GH3 cell viability by 19%, 26%, and 58%, respectively (p < 0.001). (G) DRD2 and DRD5 protein expression in MMQ and GH3 cells by western blotting. (H) Drd2 and Drd5 mRNA expression in MMQ and GH3 cells by qRT-PCR. (I) Western blotting showing DRD5 knockdown (KD) in GH3 cells by RNAi. (J) Drd5 KD in GH3 cells abolished CAB-induced growth suppression. At 12 h and 24 h of CAB treatment, Drd5 KD completely blocked growth suppression by CAB. At 48 h of CAB treatment, Drd5 KD reversed CAB-induced growth suppression by doubling the cell viability count. (K) Nonspecific RNAi had no effect on CAB-induced growth suppression in GH3 cells. NC, nonspecific negative control siRNA; Ctrl, control. **, p < 0.01; ***, p < 0.001.