CALCA and depressive disorder: Calcitonin gene-related peptide (CGRP) has proven efficacy for the preventive treatment of migraine that is associated with depression and has improved depressive-like behavior in mice with 15-day chronic restraint stress (CRS) by intracerebroventricular administration (Hashikawa-Hobara et al., 2015; Spierings et al., 2021) Among them, calcitonin and calcitonin-related peptides as small molecular peptides have been widely used in the treatment of neuropsychological diseases.