کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4356553 | 1615687 | 2006 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The effect of BAPTA and 4AP in scala media on transduction and cochlear gain
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
علم عصب شناسی
سیستم های حسی
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
We have injected by iontophoresis 4-amino-pyridine, a K+ channel blocker and BAPTA, (a Ca++ chelator), into scala media of the first three turns of the guinea pig cochlea. We measured the reduction in outer hair cell (OHC) receptor current, as indicated by cochlear microphonic measured in scala media evoked by a 207Â Hz tone, and compared this with the elevation of the cochlear action potential (CAP) threshold. We found that in the basal turn, for frequencies between 12 and 21Â kHz, CAP threshold was elevated by about 30Â dB, while in the second turn, at the 3Â kHz place, the maximum elevation was 15Â dB. In the third turn, iontophoresis of 4AP and BAPTA reduced CM by similar amounts to that in the basal and second turn, but caused negligible elevation of CAP threshold. We conclude that the gain of the cochlear amplifier is maximal for basal turn frequencies, is halved at 3Â kHz, and is reduced to close to one for frequencies below 1Â kHz (no active gain). The effect of 4AP and BAPTA on neural threshold and the receptor current represented by CM may be explained by their action on OHC transduction without the involvement of IHCs.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Hearing Research - Volume 211, Issues 1â2, January 2006, Pages 7-15
Journal: Hearing Research - Volume 211, Issues 1â2, January 2006, Pages 7-15
نویسندگان
P.M. Sellick, D. Robertson, R. Patuzzi,