SST and major depressive disorder: A decrease in SST expression in the cortex is observed in neurodegenerative and psychiatric disorders such as Alzheimer’s disease (Davies et al., 1980; Kumar, 2005), Parkinson’s disease (Epelbaum, 1986; Iwasawa et al., 2019), Huntington’s disease (Rajput et al., 2011), major depressive disorder (Rubinow et al., 1985; Tripp et al., 2011; Lin and Sibille, 2015), bipolar disorder (Fung et al., 2014; Pantazopoulos et al., 2017), and schizophrenia (Reinikainen et al., 1990; Hoftman et al., 2015).