PRESSURE AND FLOW IN THE RETINAL CIRCULATION

视网膜循环中的压力和流量

• 批准号: 2163430
• 负责人: Matthew Richard Glucksberg
• 金额: $ 11.9万
• 依托单位: NORTHWESTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-04-01 至 1997-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2163430
• 关键词: blood /plasma substitute; blood pressure; blood vessel occlusion; cats; diabetic retinopathy; disease /disorder model; fluorocarbon polymers; glaucoma; hydrostatic pressure; hyperglycemia; microcirculation; micropuncture; retina circulation; vision disorders

Disorders of the retinal microvasculature are important in many diseases which impair vision. Retinal blood flow has been studied extensively, however retinal vascular pressures, which determine both capillary perfusion and filtration pressures, have not been directly measured. The experiments described in this proposal make use of newly developed micropuncture techniques to investigate the control of microvascular blood pressure and flow in the retina. The servonull micropuncture technique, in which micropipettes are used to measure hydrostatic pressure, will be used to measure vascular pressures in the intact retina of an anesthetized cat. The proposal is divided into several parts with considerable overlap in experimental technique and scientific purpose. In part one, pressures in retinal vessels will be determined under several physiological conditions which are related to autoregulatory mechanisms. Conditions to be tested include the effects of altered blood gas tensions and hyperglycemia. In part two, we note that our preliminary studies of retinal vein pressure contradict current understanding of retinal hemodynamics and we present two possible explanations for our data and propose experiments to test our hypotheses. In part three, the effect of a new fluorocarbon-based substitute, which may prove to be useful as a treatment for retinal vascular occlusion, will be tested for its effect on microvascular pressures and flow. In part four, we will use our recently developed model of retinal vascular occlusion to assess the effects of a retinal thrombosis on retinal microvascular pressures. These studies are expected to shed light on the etiology of several diseases which have circulatory components including diabetes, glaucoma, retinal edema and retinal occlusive disease. The cat will be the animal of choice for all these studies because of the comparative similarity of its retina and retinal vasculature to those of humans.

视网膜微血管系统的紊乱在许多疾病中是重要的 会损害视力 视网膜血流已被广泛研究， 然而，视网膜血管压力，其决定了毛细血管 灌注压和滤过压尚未直接测量。 本提案中描述的实验利用了新开发的 微穿刺技术研究微血管的控制 血压和视网膜血流。 伺服微穿刺 技术，其中微量移液管用于测量流体静力学 将用于测量完整视网膜中的血管压力 一只被麻醉的猫 该提案分为几个部分，其中有相当多的重叠， 实验技术和科学目的。 第一部分，压力 将在几种生理条件下确定视网膜血管中的 与自动调节机制有关的条件。 条件 要测试的包括改变血气张力的影响， 高血糖症 在第二部分中，我们注意到，我们的初步研究 视网膜静脉压与目前对视网膜静脉压的认识相矛盾。 血液动力学，我们提出了两种可能的解释，我们的数据， 提出实验来检验我们的假设。 第三部分，效果 一种新的碳氟化合物基替代品，这可能被证明是有用的， 一种治疗视网膜血管阻塞的药物， 对微血管压力和流量的影响 在第四部分中，我们将使用 最近开发的视网膜血管阻塞模型，以评估 视网膜血栓形成对视网膜微血管压力的影响。 这些研究有望阐明几种疾病的病因 包括糖尿病，青光眼， 视网膜水肿和视网膜闭塞性疾病。 猫将成为所有这些研究的首选动物，因为 它的视网膜和视网膜血管系统与 人类