کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6382671 | 1625963 | 2013 | 11 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Ion-selective microelectrode measurements of Tl+ and K+ transport by the gut and associated epithelia in Chironomus riparius
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم کشاورزی و بیولوژیک
علوم آبزیان
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Ion-selective microelectrode measurements of Tl+ and K+ transport by the gut and associated epithelia in Chironomus riparius Ion-selective microelectrode measurements of Tl+ and K+ transport by the gut and associated epithelia in Chironomus riparius](/preview/png/6382671.png)
چکیده انگلیسی
Thallium (Tl) is a non-essential metal that is mobilized through industrial processes, subsequently entering aquatic environments where it can exert toxic effects. Although the aquatic larvae of the midge, Chironomus riparius, are exceptionally tolerant toward many waterborne non-essential metals, few studies have looked at the cellular mechanism of this tolerance. Tl+ and K+ share the same charge and have similar ionic radii, resulting in competition between these ions for K+ transporters. Using a recently developed Tl+-selective microelectrode in conjunction with the scanning ion selective electrode technique (SIET) and a two-microelectrode holder, measurements of K+ and Tl+ fluxes were made along the anal papillae and also along the isolated gut tract and Malpighian tubules (MTs) of C. riparius larvae. The MTs are a site of Tl+ secretion (i.e. from hemolymph into the tubule lumen). The major K+ transporting regions of the gut were the caecae, anterior midgut (AMG) and posterior midgut (PMG) in Tl+-naïve larvae, and Tl+ was also transported in the same direction at these locations. When the bathing saline concentration of Tl+ was increased to 50 μmol lâ1, K+ transport was inhibited at the AMG and PMG. Larvae exposed to 300 μmol lâ1 waterborne Tl+ for 48 h prior to ion flux measurements absorbed Tl+ (lumen to hemolymph) across the caecae, AMG and PMG. K+ secretion at the caecae was unaffected by Tl+ exposure, consistent with separate pathways for Tl+ and K+ transport across the caecae. By contrast, K+ flux at the AMG and PMG of Tl+-exposed larvae was impaired, suggesting that interference of Tl+ on K+ transport across these tissues may contribute to Tl+ toxicity.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Aquatic Toxicology - Volumes 138â139, 15 August 2013, Pages 70-80
Journal: Aquatic Toxicology - Volumes 138â139, 15 August 2013, Pages 70-80
نویسندگان
Ryan Belowitz, Michael J. O'Donnell,