FIG 7.

Agonist-mediated decreases in endogenous Sstr3 neuronal ciliary localization require βarr2. Hippocampal neurons from WT and βarr2-KO mice after 7 days in culture were treated with vehicle (Veh) or 10 μM SST for 40 min, fixed, and labeled with antibodies to Sstr3 and AC3 (n = 3 experiments per genotype). In vehicle- and SST-treated WT cultures, Sstr3 localized to 60.4% ± 2.4% of AC3-positive cilia (n = 369) and 41.6% ± 2.3% of AC3-positive cilia (n = 388), respectively. In vehicle- and SST-treated βarr2-KO cultures, Sstr3 localized to 50.8% ± 3.4% of AC3-positive cilia (n = 333) and 53% ± 3.4% of AC3-positive cilia (n = 324), respectively. The percentage of Sstr3-positive cilia was significantly decreased after 40 min of SST treatment in WT neuronal cultures but did not change in βarr2-KO neuronal cultures. The percentages of Sstr3-positive cilia in vehicle-treated WT and βarr2-KO neuronal cultures were not significantly different. Values are expressed as the mean ± SEM. **, significantly different results (P < 0.005).