FIELD: medicine, pharmacy, peptides. SUBSTANCE: invention relates to peptide that is a derivative of prosaposin comprising from 14 to 50 amino acids and including the following sequence: Thr-Xaa-Leu-Ile-Asp-Asn-Ala-Thr-Glu-Glu-Ile-Leu-Tyr. Invention relates also to pharmaceutical composition used for therapy of nervous or demyelinizing nervous tissue diseases and comprising indicated peptides. Invention describes also method for neuropathic pain relief in patient, method for stimulation of neuritis growth, inhibition of neurons death, stimulation of myelinization and inhibition of demyelinization of neurons and also method for inhibition of sensitive or motor neuropathy including administration of prosaposin active fragment. Claimed peptides can be used for stimulation of neurites growth, inhibition of nervous system cells death, stimulation of myelinization and inhibition of demyelinization. EFFECT: valuable medicinal properties of peptides. 27 cl, 3 dwg, 6 tbl
