SSTR4 and depressive symptom measurement: Synthetic sst4 agonists inhibit pain, inflammation (Sándor et al. 2006; Schuelert et al. 2015), depression-like behavior (Scheich et al. 2016), and as neurodegeneration and cognitive dysfunction via increasing neprilysin activity leading to decreased cortical Aβ1–42 formation in rodent models (Sandoval et al. 2011, 2012).