FIELD: medicine. SUBSTANCE: invention proposes low-molecular RNA from hair bulb cell nuclei of physiologically young animals as agent stimulating the hair growth. This RNA has 95% of low-molecular RNA, not less, containing 100-250 nucleotides and sedimentation constant 4-8 S, protein content is 5-%, not above, and trace amount of DNA. Agent is prepared from dehydrated hide of physiologically young animals no containing subcutaneous fat cellular tissue. Fragments containing hair bulbs are isolated, homogenized, proteins are separated and the end product is purified. The new biologically active substance is obtained. Agent is able to stimulate hair growth specifically, i. e. accelerate and/or induce this process. EFFECT: enhanced effectiveness of novel agent. 3 cl, 5 tbl, 3 ex
