PACAP-38 (31-38), human, mouse, rat TFA is a PAC1 receptor activator and increases the α-secretase activity. PACAP-38 (31-38), human, mouse, rat TFA elevates cytosolic Ca2+, increases proliferation and increases phosphorylation of extracellular regulates kinase (ERK) and the epidermal growth factor receptor (EGFR). PACAP-38 (31-38), human, mouse, rat TFA demonstrates potent, efficacious, and sustained stimulatory effects on sympathetic neuronal NPY and catecholamine production. PACAP-38 (31-38), human, mouse, rat TFA can be used for neurotrophic and neuroprotective research.