Protective effect of basic fibroblast growth factor on auditory hair cells after noise exposure

The purpose of this study was to observe the protective effects of basic fibroblast growth factor (bFGF) on the cells of the inner ear using in vivo experiments. The studies were carried out using guinea pigs in which bFGF or artificial perilymph was perfused into the cochlea. The compound action potential (CAP) was measured before and after exposure to a sound simulating an explosion. The difference in CAP was significant between the bFGF-perfused group and the control group (p < 0.01, t = 3.896) and between the bFGF-perfused group and the artificial perilymph-perfused group (p < 0.05, t = 2.520). The cochleae were removed and hair cell loss estimated from surface preparations. Acoustic trauma caused loss of outer hair cells in the first and second turns of the cochlea in the bFGF-perfused group and the artificial perilymph-perfused group and partial loss of inner hair cells in the control group. Treatment with bFGF reduced the loss of inner hair cells compared to that of control animals. Our results demonstrate that treatment with bFGF protects the hair cells from acoustic trauma and may facilitate the recovery of hearing.