BLOOD FLOW AND OXYGEN EXTRACTION IN CAT UVEA AT NORMAL AND HIGH INTRAOCULAR PRESSURES
BLOOD FLOW AND OXYGEN EXTRACTION IN CAT UVEA AT NORMAL AND HIGH INTRAOCULAR PRESSURES
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DOI：
10.1111/j.1748-1716.1970.tb04765.x
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发表时间：
1970-01-01
期刊：
影响因子：
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通讯作者：
BILL, A
中科院分区：
文献类型：
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作者：
ALM, A;BILL, A
在猫中测定通过葡萄膜的血流速率和通过葡萄膜的动静脉O2差。正常血流速度为1.14 ± 0.23 ml/min，正常a-v O2差值为1.02 ± 0.16体积%。O2提取为8.0 ± 0.6 μl NTP/min。动脉血氧饱和度、Po 2、Pco 2和pH分别为95.6 ± 0.3%、93 ± 3 mm Hg、25.8 ± 1.0 mm Hg，和7.44 ± 0.01单位。人工升高眼压降低了葡萄膜血流速度，增加了a-v O2差。O2提取是相对恒定的血液流速高于0.3-0.5 ml/min。在较低的流速，O2提取减少，尽管静脉O2浓度高。从脉络膜静脉采集的血液比从巩膜内静脉丛采集的血液的O2浓度略高。平均动脉血压的降低导致葡萄膜血流量的减少，从而降低了从脉络膜收集的血液和离开前葡萄膜的血液中的O2含量。结果表明，在低灌注压力下，尽管静脉血含氧相对较好，但葡萄膜血管供应的某些组织中存在缺氧。
The rate of blood flow through the uvea and the arterio‐venous O2difference across the uveal tract were determined in cats. The normal rate of blood flow was 1.14 ± 0.23 ml/min and the normal a‐v O2difference was 1.02 ± 0.16 volume per cent. The O2extraction was 8.0 ± 0.6 μl NTP/min. The arterial O2saturation, Po2, Pco2, and pH were 95.6 ± 0.3 per cent, 93 ± 3 mm Hg, 25.8 ± 1.0 mm Hg, and 7.44 ± 0.01 units, respectively. An artificial rise in eye pressure reduced the rate of uveal blood flow and increased the a‐v O2difference. The O2extraction was relatively constant at blood flow rates above 0.3–0.5 ml/min. At lower flow rates the O2extraction decreased in spite of a high venous O2concentration. Blood collected from the choroidal veins had a slightly higher O2concentration than blood collected from the intrascleral venous plexus. A reduction in uveal blood flow, produced by a reduction in the mean arterial blood pressure, reduced the O2content both in blood collected from the choroid and in blood leaving the anterior uvea. The results suggest that at low perfusion pressures there is anoxia in some tissue supplied by the uveal vessels, in spite of a relatively well oxygenated venous blood.