title: Attenuation of streptomycin ototoxicity by tetramethylpyrazine and its effect on K⁺ channels in the outer hair cells of guinea pig cochlea.
abstract: In order to elucidate the mechanism underlying the attenuation of streptomycin ototoxicity by tetramethylpyrazine (TMP), the present study investigated the effect of TMP on the outward K(+) current in the outer hair cells of guinea pig cochlea. Sixty guinea pigs were divided into 6 groups randomly. Auditory brainstem response (ABR) was used to observe the change in thresholds and to evaluate ototoxicity induced by streptomycin. Whole-cell patch-clamp technique was used to observe the effect of TMP on outward K(+) current in isolated outer hair cells. The results showed that TMP attenuated the threshold shift caused by streptomycin and increased the amplitudes of Ca(2+)-sensitive K(+) current [I(K(Ca))] in the outer hair cells. The present data suggest that TMP displays anti-ototoxicity induced by streptomycin. The augmented amplitudes of I(K(Ca)) of the outer hair cells induced by TMP may be one of the mechanisms underlying its ototoxicity-attenuating effect.
authors: Department of Physiology, School of Basic Medical Sciences, China Medical University, Shenyang 110001, China. tanghaocn2003@yahoo.com.cn
authors: Hao
authors: H
authors: Tang
authors: Gui-Ying
authors: GY
authors: Cui
authors: Li-Juan
authors: LJ
authors: Shi
authors: Qing-Hua
authors: QH
authors: Gao
authors: Yu
authors: Y
authors: Cao
mesh_terms: D000818:Animals; D001309:Auditory Threshold; D003051:Cochlea / Q000166:cytology*; D016057:Evoked Potentials, Auditory, Brain Stem; D006168:Guinea Pigs; D018072:Hair Cells, Auditory, Outer / Q000187:drug effects*; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000378:metabolism*; D011719:Pyrazines; D013307:Streptomycin / Q000633:toxicity*
chemical_list: D015221:Potassium Channels; D011719:Pyrazines; C017953:tetramethylpyrazine; D013307:Streptomycin