Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) is a synthetic heptapeptide analog of the endogenous immunomodulatory peptide tuftsin, engineered with a C-terminal Pro-Gly-Pro tripeptide extension to enhance stability and CNS penetration. Unlike traditional anxiolytics, Selank modulates anxiety and stress responses through multiple neurotransmitter systems without causing sedation, cognitive impairment, or dependence. This research peptide demonstrates unique anxiolytic, nootropic, and immunomodulatory properties, making it an exceptional tool for investigating the neurobiology of anxiety, stress adaptation, and cognitive-emotional interactions.