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Background;There are many studies that have reported the relation with diabetes and hearing loss. But, we still have a little knowledge about the pathophysiology of hearing aggravation in diabetes condition. Therefore, we investigated the impact of streptozotocininduced type 1 diabetes on the recovery from noise-induced hearing loss and synaptopathy in rat model after transient threshold shift noise expose. Marterial and Methods; 14 Sprague-Dawley rats (SD) rats treated with streptozotocin were used and then measured blood glucose and body weight every week. We confirm streptozotocin-induced type 1 diabetes rat model. We designed two conditions; acute (diabetes for 4 weeks), chronic (diabetes for 12 weeks) model. Click and tone hearing thresholds using TDT-ABR at frequencies of 4, 8, 12, 16, 32 kHz were measured before and 1, 3, 7, 14 days after transient threshold shift (16 kHz narrow band noise, 105 dB, for 2h) noise exposure. The P1 amplitude of ABR were measured at frequencies of 4, 8, 12, 16, 32 kHz at 1, 3, 7 and 14 days after TTSnoise exposure. Immunohistochemistry of CtBP2 and and phalloidin were done. Results; Hearing threshold in the control group was complete recovery but 16 kHz in acute diabetics model and 16 and 32 kHz in chronic diabetics model did not show the hearing recovery. P1 amplitude of ABR after noise exposure decreased in both group and the recovery of amplitude was definite and fast in control group but not in both DM groups. The P1 amplitude of ABR were significantly higher in DM group than control group at 4, 8 kHz. Conclusion; The P1 amplitude decreased after TTS noise exposure and then slowly recovered until 2 weeks. The recovery rate of P1 amplitude was faster in control group than DM group. We guess that synapthopaty maybe has important role in this results. [ABSTRACT FROM AUTHOR]