Oxygen-deficient metabolism and corneal edema.
Oxygen-deficient metabolism and corneal edema.
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DOI：
10.1016/j.preteyeres.2011.07.001
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发表时间：
2011-11
影响因子：
17.8
通讯作者：
Radke CJ
中科院分区：
文献类型：
--
作者：
Leung BK;Bonanno JA;Radke CJ
佩戴低透氧性软性隐形眼镜会使角膜明显肿胀，即使在睁眼时也是如此。尽管缺氧性角膜水肿已有充分记录，但基于潜在代谢反应的自洽定量预测尚不可用。我们提出了人类角膜的生化描述，通过水、盐和呼吸代谢物的耦合运输来量化缺氧肿胀。葡萄糖的有氧和无氧消耗以及酸中毒和 pH 缓冲均纳入七层角膜模型（前房、内皮、基质、上皮、晶状体后泪膜、隐形眼镜和晶状体前泪膜）中。角膜肿胀是通过水、溶解盐、尤其是代谢物的耦合运输以及内皮和上皮的膜运输阻力来预测的。在内皮细胞中，Na+/K+ - ATP 酶生电通道主动将碳酸氢根离子从基质转运至前房。正如 Kedem-Katchalsky 膜传输形式所捕获的那样，活性碳酸氢根离子通量提供了角膜液泵出所需的驱动力，以匹配基质的渗漏趋势。缺氧期间乳酸离子产生增加，渗透压降低了泵出速率，需要基质膨胀至更高的含水量。预测葡萄糖、水、氧气、二氧化碳、水合氢离子、乳酸根、碳酸氢根、钠离子和氯离子的浓度分布，以及静电势和压力分布。尽管内皮细胞的活性碳酸氢根离子泵将碳酸氢盐驱动到房水中，但我们发现碳酸氢根离子净流入角膜，可以防止酸中毒。我们首次根据基本的生物物理化学原理预测佩戴软性隐形眼镜时的角膜肿胀。我们还成功预测高渗泪液可以减轻隐形眼镜引起的水肿。
Wear of low-oxygen-transmissible soft contact lenses swells the cornea significantly, even during open eye. Although oxygen-deficient corneal edema is well-documented, a self-consistent quantitative prediction based on the underlying metabolic reactions is not available. We present a biochemical description of the human cornea that quantifies hypoxic swelling through the coupled transport of water, salt, and respiratory metabolites. Aerobic and anaerobic consumption of glucose, as well as acidosis and pH buffering, are incorporated in a seven-layer corneal model (anterior chamber, endothelium, stroma, epithelium, postlens tear film, contact lens, and prelens tear film). Corneal swelling is predicted from coupled transport of water, dissolved salts, and especially metabolites, along with membrane-transport resistances at the endothelium and epithelium. At the endothelium, the Na+/K+ - ATPase electrogenic channel actively transports bicarbonate ion from the stroma into the anterior chamber. As captured by the Kedem–Katchalsky membrane-transport formalism, the active bicarbonate-ion flux provides the driving force for corneal fluid pump-out needed to match the leak-in tendency of the stroma. Increased lactate-ion production during hypoxia osmotically lowers the pump-out rate requiring the stroma to swell to higher water content. Concentration profiles are predicted for glucose, water, oxygen, carbon dioxide, and hydronium, lactate, bicarbonate, sodium, and chloride ions, along with electrostatic potential and pressure profiles. Although the active bicarbonate-ion pump at the endothelium drives bicarbonate into the aqueous humor, we find a net flux of bicarbonate ion into the cornea that safeguards against acidosis. For the first time, we predict corneal swelling upon soft-contact-lens wear from fundamental biophysico-chemical principles. We also successfully predict that hypertonic tear alleviates contact-lens-induced edema.
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影响因子：
3.4
作者：
FATT, I
通讯作者：
FATT, I
DOI：
10.1115/1.2798004
发表时间：
1998-06-01
影响因子：
1.7
作者：
Bryant, MR;McDonnell, PJ
通讯作者：
McDonnell, PJ
影响因子：
3.4
作者：
CHEN, FS;MAURICE, DM
通讯作者：
MAURICE, DM
影响因子：
3.4
作者：
CONROY, CW;BUCK, RH;MAREN, TH
通讯作者：
MAREN, TH
影响因子：
1.4
作者：
Chhabra, Mahendra;Prausnitz, John M.;Radke, Clayton J.
通讯作者：
Radke, Clayton J.