VISUAL TRANSDUCTION IN RETINAL PHOTORECEPTORS

拟议研究的长期目标是详细了解 脊椎动物视觉信号转导的细胞机制 视网膜光感受器 具体目标是： i）了解更多关于细胞内钙的调节， 感光细胞中的钠钙交换器，看看是否有 视杆细胞和视锥细胞在这方面的差异可能解释了它们的一些差异。 光敏感性和响应动力学的差异， ii）了解更多关于两个视杆中的光敏电导的信息， 圆锥体和 iii）了解更多关于光激活的功能成分 环GMP反应级联（即GTP结合蛋白， 磷酸二酯酶和48K蛋白），并进行比较 视杆细胞和视锥细胞与这些成分有关。 视觉传导机制的详细知识对于 了解影响光感受器的各种疾病状态， 为他们制定补救措施。 该方法将主要涉及电生理记录， 采用吸移管和膜片钳技术。

The long-term objective of the proposed research is to understand in detail the cellular mechanisms underlying visual transduction in vertebrate retinal photoreceptors. The specific aims are: i) to understand more about the regulation of intracellular calcium by the sodium-calcium exchanger in the photoreceptors, and to see if any difference in this regard between rods and cones may explain some of their differences in light sensitivity and response kinetics, ii) to learn more about the light-sensitive conductance in both rods and cones, and iii) to learn more about the functional constituents in the light-activated cyclic GMP reaction cascade (i.e. GTP-binding protein, the phosphodiesterase and the 48K protein), and to make a comparison between rods and cones concerning these constituents. A detailed knowledge of the visual transduction mechanism is important for understanding various disease states which affect photoreceptors, and for devising remedies for them. The methodology will involve mainly electrophysiological recordings, employing both suction-pipet and patch-clamp techniques.