sildenafil-citrate and Hearing-Loss--Noise-Induced

To study the effects of sildenafil on morphology to noise-induced hearing loss in guinea pigs.. Guinea pigs were randomly divided into control group, noise exposure group and the sildenafil treatment group, 12 in each group. a week after white noise exposure of 110 dB, sildenafil (10 mg/kg x d) and NS (4 ml/kg x d) were injected into guinea pigs of the sildenafil treatment group and noise exposure group respectively for four continuous weeks. ABR thresholds were measured respectively prior to the experiment, 1 week post-noise, 1, 2 and 4 weeks post-drugs, the changes of cochlea hair cells were also observed with a scan electron microscope (SEM) and light microscope.. The ABR threshold shifts in the sildenafil treatment group were significantly fewer than that in the noise exposure group. SEM showed that hear hair of the inner and outer hair cells in noise exposure group displayed mess, fusion and imperfections. In the sildenafil treatment group, the hair cells displayed slight pathological changes, there wasn't significant differents comparied with normal group. The number of OHCs were relatively stable in the normal group, while the obvious OHC loss was observed in other groups. There was significant difference among the three groups, however, the OHC loss in the sildenafil treatment group was not significantly different to that in the noise exposure (P > 0.05).. Sildenafil can significantly protect against noise-induced hearing loss.

Topics: Animals; Guinea Pigs; Hair Cells, Auditory, Outer; Hearing Loss, Noise-Induced; Noise; Sildenafil Citrate

To investigate the protective effects of sildenafil to noise-induced hearing loss in guinea pigs.. Guinea pigs were randomly divided into control group, noise exposure group and the sildenafil treatment group, with 10 in each group. One week after the exposure of 110 dB (A) white noise, sildenafil [10 mg/(kg×d)] and normal saline [4 ml/(kg×d)] were injected into guinea pigs of noise plus sildenafil group (NSG) and noise plus normal saline group(NNG) respectively. One week after noise exposure to four weeks continuous administration. ABR thresholds were measured respectively prior to the experiment, 1 week post-noise, 1, 2 and 4 weeks post-drugs. The changes of cochlea hair cells were also observed by scanning electron microscope (SEM).. After noise exposure, the ABR threshold shifts in NSG were significantly fewer than that in the NNG. An average of 19.1 dB in NNG compared with 19.8 dB in NSG. Four weeks after exposure, the threshold shifts were become larger to 22.0 dB in NNG while become smaller to 4.8 dB in NSG. Compared NNG with NSG, in addition to noise exposure time point, there were statistically significant differences in the rest time points after administration of the ABR threshold (P<0.05). SEM showed that the inner and outer hair cells in NNG displayed mess, fusion and imperfections. In NSG, the hair cells displayed slight pathological changes, there was no significant difference when compared with control group.. Sildenafil is able to reduce the ascending of ABR thresholds shift, and it can significantly protect against noise-induced hearing loss.

Topics: Animals; Auditory Threshold; Cochlea; Guinea Pigs; Hair Cells, Auditory; Hearing Loss, Noise-Induced; Piperazines; Purines; Sildenafil Citrate; Sulfones