Thurlow G A, Cooper R M
Psychology Department, University of Calgary, Alberta, Canada.
J Comp Neurol. 1991 Apr 22;306(4):697-707. doi: 10.1002/cne.903060411.
We examined the effects of loss of monocular retinal activity on 2-deoxyglucose (2-DG) uptake in the adult rat geniculostriate system. Of particular interest was whether the influence of the normally functioning eye changed during long-term contralateral retinal silence. Group 1 rats were subjected to short-term (24 hours) and group 2 rats to long-term (21-90 days) monocular tetrodotoxin (TTX) blockade, and metabolic activity was assessed during exposure to square-wave gratings. Group 1 rats exhibited patterns of cortical glucose utilization commensurate with complete monocular loss of retinal activity: minimal 2-DG uptake in contralateral monocular area 17 and dorsal lateral geniculate nucleus (LGN), and a bilateral depression in the binocular regions; 2-DG uptake was highest in the monocular regions fed by the stimulated normal eye (in both area 17 and the LGN) and these regions appeared unaffected by the monocular blockade. After repeated injections of TTX (group 2), metabolic activity in binocular area 17 and binocular LGN increased bilaterally relative to the metabolically active monocular regions contralateral to the normal eye. Group 3 rats were monocularly TTX-injected for 30 or 60 days, and, 24 hours before 2-DG, all retinal activity was eliminated by means of binocular TTX injections or binocular enucleation. Glucose utilization in the binocular regions of both area 17 and the LGN in these rats was depressed to levels seen in monocular area 17 after complete and recent loss of activity from the contralateral eye, indicating that the metabolic increase which occurred in the binocular regions during long-term monocular retinal blockade was dependent upon the neuronal processing of retinal information from the non-TTX eye. We conclude that, in the adult rat, an activity-dependent, physiologically based shift in ocular influence occurred in the binocular geniculostriate system during long-term monocular retinal inactivation.
我们研究了成年大鼠膝状体纹状体系统中单侧视网膜活动丧失对2-脱氧葡萄糖（2-DG）摄取的影响。特别令人感兴趣的是，在长期对侧视网膜沉默期间，正常功能眼的影响是否会发生变化。第1组大鼠接受短期（24小时）单侧河豚毒素（TTX）阻断，第2组大鼠接受长期（21 - 90天）单侧TTX阻断，并在暴露于方波光栅期间评估代谢活性。第1组大鼠表现出与视网膜活动完全单侧丧失相称的皮质葡萄糖利用模式：对侧单眼区域17和背外侧膝状核（LGN）的2-DG摄取极少，双眼区域出现双侧抑制；在由受刺激的正常眼供血的单眼区域（区域17和LGN）中，2-DG摄取最高，并且这些区域似乎不受单侧阻断的影响。在重复注射TTX后（第2组），相对于正常眼对侧的代谢活跃单眼区域，双眼区域17和双眼LGN的代谢活性双侧增加。第3组大鼠单侧注射TTX 30或60天，并且在注射2-DG前24小时，通过双眼注射TTX或双眼摘除眼球消除所有视网膜活动。这些大鼠的区域17和LGN的双眼区域中的葡萄糖利用被抑制到对侧眼完全且近期丧失活动后在单眼区域17中观察到的水平，这表明在长期单侧视网膜阻断期间双眼区域中发生的代谢增加依赖于来自非TTX眼的视网膜信息的神经元处理。我们得出结论，在成年大鼠中，在长期单侧视网膜失活期间，双眼膝状体纹状体系统中发生了基于活动的、生理基础的眼影响转移。
