An alternative phototransduction model for human rod and cone ERG a-waves: Normal parameters and variation with age
An alternative phototransduction model for human rod and cone ERG a-waves: Normal parameters and variation with age
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DOI：
10.1016/0042-6989(95)00327-4
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发表时间：
1996-08-01
期刊：
影响因子：
1.8
通讯作者：
Jacobson, SG
中科院分区：
文献类型：
--
作者：
Cideciyan, AV;Jacobson, SG
最近发展了对cGMP光传导级联中的活化反应的定量描述[Lamb&Pugh(1992)]。生理学杂志，449,719-758]，当应用于人类视网膜电信号a波时，该模型的广泛使用的简化形式提供了对除由非常高的能量刺激引起的波形之外的所有波形的良好描述，在当前的研究中探索了这些不匹配的基础，并导出了另一种光转导模型，该模型保留了量化方面，但避免了先前所做的某些简化假设，新模型在大范围的刺激能量范围内很好地描述了杆和锥隔离的a波，直到那些导致显著漂白的刺激能量。为了便于临床应用，制定了一种简短的测试方案，并提供了广泛年龄范围内视杆和视锥传导参数的正常数据。在所研究的正常受试者样本中，视杆和视锥a波的最大幅度和视锥a波的灵敏度不随年龄而改变，视杆a波的灵敏度存在与年龄相关的下降，且大于单纯视网膜前吸收的预期。版权所有(C)1996爱思唯尔科学有限公司。
A quantitative description of the activation reactions in the cGMP phototransduction cascade has been recently developed [Lamb & Pugh (1992). Journal of Physiology, 449, 719-758], When applied to the human electroretinogram a-wave, the widely used simplified form of this model provides a good description of all waveforms except those elicited with very high energy stimuli, The basis for these misfits at high energies is explored in the current study and an alternative model of phototransduction is derived that retains the quantitative aspects but avoids certain simplifying assumptions previously made, The new model describes well both rod- and cone-isolated a-waves over a large range of stimulus energies extending up to those that cause significant bleaching. To facilitate clinical application of this methodology, a short test protocol is developed and normal data for rod and cone transduction parameters are provided over a wide age range, In the sample of normal subjects studied, maximum amplitude of rod and cone a-waves and sensitivity of the cone a-wave do not change with age, An age-related decline in rod a-wave sensitivity is present and it is greater than that expected from pre-retinal absorption alone. Copyright (C) 1996 Elsevier Science Ltd.