ELECTROPHYSIOLOGY & BIOPHYSICS OF CORNEAL WOUND HEALING

电生理学

• 批准号: 2163882
• 负责人: MITCHELL A WATSKY
• 金额: $ 8.7万
• 依托单位: UNIVERSITY OF TENNESSEE HEALTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-06-01 至 1998-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2163882
• 关键词: arachidonate; biophysics; connective tissue cells; cornea; corneal endothelium; cyclic AMP; electrophysiology; eye pharmacology; human tissue; ion transport; laboratory rabbit; membrane channels; micromanipulator; perfusion; personal computers; second messengers; voltage /patch clamp; voltage gated channel; wound healing

Following injury, whether it be the result of trauma, surgery, or infection, the cornea utilizes a variety of cellular mechanisms to repair itself. These events include reepithelialization, collagen repair via keratocytes and endothelium, and repopulation of the endothelium in areas in which it has been denuded. This process can be quite effective and often leads to complete healing of the cornea with no associated visual impairment. Unfortunately, the wound repair process can also result in stromal edema, scarring, ulceration, or in the case of refractive surgical procedures and penetrating keratoplasty, unpredictable and possibly fluctuating refractive errors. To better understand and possibly to better control the wound healing process, an understanding of the basic cellular mechanisms of corneal wound healing is essential. Ion channels in cellular membranes have been shown to be important mediators in events such as cell activation, mitogenesis and cell proliferation, migration, volume regulation, secretion, and responses to growth factors. Because all of these events are involved in the response of keratocytes and endothelial cells during the corneal wound healing process, the understanding of the interaction between ion channels and these events is crucial. Preliminary data shows that surgically wounded rabbit corneal endothelial cells have different ionic currents than those in the non-wounded control eye. Interestingly, these currents are similar to those seen in cultured endothelial cells. In keratocytes, preliminary data shows that fetal bovine serum stimulation, a known "activator" of this cell type, causes a rapid increase in the amplitude of the membrane currents. This effect appears to be associated with both activation of a new channel type as well as the voltage sensitive Na+ channel. A similar current activation is observed when 8-bromo-cAMP is added to the bath. The specific aims of this grant are designed to specifically address the biophysical nature and physiological relevance of many of these preliminary findings. Initial studies will utilize whole cell and single channel patch clamp techniques to characterize and determine the mechanisms of injury induced changes in endothelium and keratocyte ion channel activity. In addition, the physiological and pharmacological significance of these changes will be examined using in-vivo wound healing studies as well as in-vitro perfusion studies.

受伤后，无论是创伤、手术还是 感染时，角膜利用各种细胞机制来修复 本身 这些事件包括上皮再生、胶原修复， 角膜细胞和内皮细胞，以及区域中内皮细胞的再增殖 在那里，它被剥夺了。 这个过程可能非常有效， 通常导致角膜完全愈合， 损伤 不幸的是，伤口修复过程也可能导致 基质水肿、瘢痕形成、溃疡，或屈光不正 手术和穿透性角膜移植术，不可预测， 可能是波动的屈光不正。 更好地理解和 为了更好地控制伤口愈合过程， 角膜伤口愈合的基本细胞机制是必不可少的。 细胞膜中的离子通道已被证明是重要的 在诸如细胞活化、有丝分裂和细胞增殖等事件中， 增殖、迁移、体积调节、分泌和对 生长因子 因为所有这些事件都涉及到 角膜创伤愈合过程中角膜细胞和内皮细胞的变化 过程，了解离子通道和 这些事件至关重要。 初步数据显示， 兔角膜内皮细胞的离子电流与 在未受伤的对照眼中。 有趣的是，这些电流 类似于在培养的内皮细胞中观察到的那些。 在角膜细胞中， 初步数据显示，胎牛血清刺激，一种已知的 这种细胞类型的“激活剂”，导致振幅迅速增加 的膜电流。 这种影响似乎与两种 激活新的通道类型以及电压敏感的Na+ 频道 当8-溴-cAMP被激活时，观察到类似的电流激活。 添加到浴缸。 该补助金的具体目的是 具体阐述生物物理性质和生理相关性， 许多这些初步发现。 初步研究将利用全细胞和单通道膜片钳 描述和确定损伤诱导机制的技术 内皮细胞和角膜细胞离子通道活性的变化。 此外，本发明还提供了一种方法， 这些变化的生理学和药理学意义将 使用体内伤口愈合研究以及体外 灌注研究。