Overview
Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) derived from amino acids 4–10 of adrenocorticotropic hormone (ACTH). The C-terminal Pro-Gly-Pro tail extends plasma stability without melanocortin receptor activity.
Mechanism
Animal studies report upregulation of BDNF and NGF expression in the hippocampus, modulation of dopaminergic and serotonergic turnover, and reduced enkephalin degradation. These pathways underpin its use as a reference compound in attention, ischemia, and neuroprotection models.
Notes for the lab
Most published rodent and intranasal pharmacokinetic data use very small doses by body weight. Reconstitute in bacteriostatic water and store cold; the molecule is stable but susceptible to oxidation of the N-terminal methionine.