Submit a Letter to the Editor for:
Tomohiko Usui, Masumi Hara, Hiroaki Satoh, Nobuo Moriyama, Humie Kagaya, Shiro Amano, Tetsuro Oshika, Yasuo Ishii, Nobuhiro Ibaraki, Chiaki Hara, Motoei Kunimi, Eisei Noiri, Kazuhisa Tsukamoto, Jun Inatomi, Hayato Kawakami, Hitoshi Endou, Takashi Igarashi, Astuo Goto, Toshiro Fujita, Makoto Araie, George Seki
J Clin Invest. 2001;
108(1):107
doi:10.1172/JCI11869
Abstract |
Full text
|
PDF

P
roximal renal tubular acidosis associated with ocular abnormalities such as band keratopathy, glaucoma, and cataracts is caused by mutations in the Na+-HCO3– cotransporter (NBC-1). However, the mechanism by which NBC-1 inactivation leads to such ocular abnormalities remains to be elucidated. By immunological analysis of human and rat eyes, we demonstrate that both kidney type (kNBC-1) and pancreatic type (pNBC-1) transporters are present in the corneal endothelium, trabecular meshwork, ciliary epithelium, and lens epithelium. In the human lens epithelial (HLE) cells, RT-PCR detected mRNAs of both kNBC-1 and pNBC-1. Although a Na+-HCO3– cotransport activity has not been detected in mammalian lens epithelia, cell pH (pHi) measurements revealed the presence of Cl–-independent, electrogenic Na+-HCO3– cotransport activity in HLE cells. In addition, up to 80% of amiloride-insensitive pHi recovery from acid load in the presence of HCO3–/CO2 was inhibited by adenovirus-mediated transfer of a specific hammerhead ribozyme against NBC-1, consistent with a major role of NBC-1 in overall HCO3– transport by the lens epithelium. These results indicate that the normal transport activity of NBC-1 is indispensable not only for the maintenance of corneal and lenticular transparency but also for the regulation of aqueous humor outflow.
Guidelines:
The Editorial Board will only consider letters that we deem relevant and of interest to our readers. We will not post data that have not been subjected to peer review, nor will we post letters that are essentially a reiteration of another letter. All accepted letters will be posted on our website within one week of acceptance. The Editors reserve the right to edit any letter for length, content, and clarity. Authors of all accepted letters will be asked to preview any changes. Authors will be notified by e-mail if their letters were not accepted. As this is a final decision, no appeals will be considered.
Specific requirements: All letters must be 400 words or fewer. You may enter the letter as plain text or HTML, if you wish. The author's name and e-mail address are required, and will be posted with the letter. All possible conflicts of interest must be noted, even if they are not posted. If you wish to include a figure (keep in mind that non-peer-reviewed data will not be posted), please contact the editor directly at editors@the-jci.org.