Keywords: پپتید ناشی از خواب دلتا; Peptides; Blood–brain barrier; AJ Kastin; Delta sleep-inducing peptide; Regulatory proteins; CytokinesBBB, blood–brain barrier; BUI, brain uptake index; CNS, central nervous system; CSF, cerebrospinal fluid; DSIP, delta sleep-inducing peptide; IL, interle