Jin N, Stjernschantz J
Department of Neuroscience, Uppsala University, Uppsala, Sweden.
Exp Eye Res. 2000 Sep;71(3):233-8. doi: 10.1006/exer.2000.0871.
The purpose of the present study was to determine the regional blood flow in the myopic chick eye during and after short-term monocular form deprivation. Chicks were monocularly form-deprived by covering one eye with a translucent occluder for 7-10 days. The anterior chamber-lens distance, the vitreous chamber length and the axial length of the eye were measured by ultrasonography, the equatorial diameter was measured with calipers and the size of the eye was estimated by weighing. The regional blood flow in the eye was determined with radioactively-labelled microspheres in three groups of animals: a group of chicks wearing an occluder (n = 10), a group of chicks in which the occluder was removed 7 or 24 hr prior to the blood flow determination (n = 9), and a group of age-matched control chicks without occluder (n = 9). Monocular form deprivation increased the axial length 0.64 +/- 0.06 and 0.56 +/- 0.09 mm compared to the contralateral control eye in the two groups of chicks wearing an occluder (P < 0.001). Both the equatorial diameter and the weight of the eye increased significantly (P < 0.001). Removal of the occluder tended to reduce the difference in the vitreous chamber length during the first 24 hr. There was no statistically significant difference in the blood flow of the anterior uvea, choroid, pecten or the sclera between the form-deprived and contralateral control eyes (P > 0.05, n = 10), but when comparing to the control group, the blood flow was significantly (P < 0.05) reduced in the choroid of the occluded eye. A similar tendency was found in the anterior uvea. When the blood flow was measured 7-24 hr after the removal of the occluder, a marked increase was found in the blood flow of the choroid of both eyes compared to the situation during occlusion (P < 0.001), and to the control group (P < 0.05). In the pecten a significant (P < 0.05) increase of the blood flow in comparison to the situation during occlusion and the control group was detected after removal of the occluder, and a similar change was found in the contralateral control eye, but it did not reach statistical significance. In the anterior uvea and sclera the blood flow was also significantly (P < 0.05) or almost significantly increased after removal of the occluder in both eyes. The arterial blood pressure was 79 +/- 2, 88 +/- 2 and 99 +/- 5 mmHg in the control group, the group with monocular occlusion, and the group in which the occluder was removed, respectively.Thus, monocular form deprivation in the chick reduced the choroidal blood flow, and a similar tendency was found in the anterior uvea. However, there was no statistically significant difference in blood flow between the form-deprived and contralateral control eyes. Removal of the occluder increased the blood flow in all tissues, notably the choroid and pecten. Generally the changes in blood flow seemed to be bilateral, despite monocular occlusion.
本研究的目的是确定短期单眼形觉剥夺期间及之后近视雏鸡眼睛的局部血流情况。通过用半透明眼罩遮盖一只眼睛7 - 10天，使雏鸡单眼形觉剥夺。用超声测量前房-晶状体距离、玻璃体腔长度和眼轴长度，用卡尺测量赤道直径，通过称重估计眼睛大小。用放射性标记微球测定三组动物眼睛的局部血流：一组佩戴眼罩的雏鸡（n = 10），一组在血流测定前7或24小时摘除眼罩的雏鸡（n = 9），以及一组年龄匹配的未佩戴眼罩的对照雏鸡（n = 9）。与两组佩戴眼罩的雏鸡对侧对照眼相比，单眼形觉剥夺使眼轴长度分别增加了0.64±0.06和0.56±0.09毫米（P < 0.001）。赤道直径和眼睛重量均显著增加（P < 0.001）。摘除眼罩在最初24小时内倾向于减少玻璃体腔长度的差异。形觉剥夺眼与对侧对照眼在前葡萄膜、脉络膜、栉膜或巩膜的血流方面无统计学显著差异（P > 0.05，n = 10），但与对照组相比，被遮盖眼的脉络膜血流显著减少（P < 0.05）。在前葡萄膜也发现了类似趋势。在摘除眼罩7 - 24小时后测量血流时，与遮盖期间相比，双眼脉络膜血流显著增加（P < 0.001），与对照组相比也显著增加（P < 0.05）。在栉膜，与遮盖期间和对照组相比，摘除眼罩后血流显著增加（P < 0.05），对侧对照眼也有类似变化，但未达到统计学显著水平。在双眼摘除眼罩后，前葡萄膜和巩膜的血流也显著（P < 0.05）或几乎显著增加。对照组、单眼遮盖组和摘除眼罩组的动脉血压分别为79±2、88±2和99±5毫米汞柱。因此，雏鸡单眼形觉剥夺会减少脉络膜血流，在前葡萄膜也发现了类似趋势。然而，形觉剥夺眼与对侧对照眼在血流方面无统计学显著差异。摘除眼罩会增加所有组织的血流，尤其是脉络膜和栉膜。尽管是单眼遮盖，但一般血流变化似乎是双侧性的。
