Exposure to low-dose barium by drinking water causes hearing loss in mice

Nobutaka Ohgami, Sohjiro Hori, Kyoko Ohgami, Haruka Tamura, Toyonori Tsuzuki, Shoko Ohnuma, Masashi Kato

研究成果: ジャーナルへの寄稿学術論文査読

37 被引用数 (Scopus)

抄録

Purpose: We continuously ingest barium as a general element by drinking water and foods in our daily life. Exposure to high-dose barium (>100. mg/kg/day) has been shown to cause physiological impairments. Direct administration of barium to inner ears by vascular perfusion has been shown to cause physiological impairments in inner ears. However, the toxic influence of oral exposure to low-dose barium on hearing levels has not been clarified in vivo. We analyzed the toxic influence of oral exposure to low-dose barium on hearing levels and inner ears in mice. Experimental design: We orally administered barium at low doses of 0.14 and 1.4. mg/kg/day to wild-type ICR mice by drinking water. The doses are equivalent to and 10-fold higher than the limit level (0.7. mg/l) of WHO health-based guidelines for drinking water, respectively. After 2-week exposure, hearing levels were measured by auditory brain stem responses and inner ears were morphologically analyzed. After 2-month exposure, tissue distribution of barium was measured by inductively coupled plasma mass spectrometry. Results: Low-dose barium in drinking water caused severe hearing loss in mice. Inner ears including inner and outer hair cells, stria vascularis and spiral ganglion neurons showed severe degeneration. The Barium-administered group showed significantly higher levels of barium in inner ears than those in the control group, while barium levels in bone did not show a significant difference between the two groups. Barium levels in other tissues including the cerebrum, cerebellum, heart, liver and kidney were undetectably low in both groups. Conclusions: Our results demonstrate for the first time that low-dose barium administered by drinking water specifically distributes to inner ears resulting in severe ototoxicity with degeneration of inner ears in mice.

本文言語英語
ページ(範囲)1276-1283
ページ数8
ジャーナルNeuroToxicology
33
5
DOI
出版ステータス出版済み - 10-2012
外部発表はい

All Science Journal Classification (ASJC) codes

  • 神経科学一般
  • 毒物学

フィンガープリント

「Exposure to low-dose barium by drinking water causes hearing loss in mice」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル