An 18-mer peptide derived from the neurotrophic region of prosaposin (PS-pep) preventshearing loss and cochlear damage due to transient cochlear ischaemia by activating an anti-apoptotic pathway. PS-pep is a potent candidate molecule for alleviating ischaemia-induced hearing loss.PS-pep was investigated for its protective effects against ischaemia-induced hearing loss and cochlear damage.Ischaemia was induced in both cochleae in Mongolian gerbils by pulling the ligatures around both vertebral arteries inan anterior direction using 5 g weights for 15 min. PS-pep was synthesized artificially and administered subcutaneously four times after the induction of transient cochlear ischaemia.An increase in the auditory brainstem response threshold was alleviated in animals treated with 2.0 mg/kg PS-pep. Histological examinations conducted on day 7 showed that the loss of inner hair cells (IHCs) was more prominent than that of outer hair cells. Higher doses of PS-pep significantly alleviated IHC loss. An increase in the anti-apoptotic factorbcl-2 was also noted in the IHCs treated with PS-pep.