RUI: Pigment Granule Dispersion in Teleost Retinal Pigment Epithelium: Cholinergic Mechanisms

这项拟议中的研究着眼于当光线照射到眼睛时会发生什么。研究将研究当眼睛适应不断变化的光线水平时发生了什么，以及这些信息是如何在视网膜和视网膜色素上皮（RPE）之间传递的。它将瞄准视网膜用来与RPE交流的微小化学信使。RPE是靠近视网膜的一层薄薄的组织。研究人员将使用鱼眼作为这些研究的组织来源。与人类的眼睛不同，鱼的眼睛有固定直径的瞳孔。鱼不像人那样通过放大或缩小瞳孔来适应光线的变化。相反，它们重新排列它们的感光感受器和RPE中的色素颗粒，以便将适量的光传递给最适合这项工作的感光感受器——视杆细胞或视锥细胞。在光线下，RPE中的色素颗粒扩散成手指状的延伸，与视杆细胞和视锥细胞交织在一起。这些重排使RPE遮蔽了杆状光感受器，杆状光感受器专门用于夜视，同时仍然允许锥状光感受器，明亮的光和彩色的视觉专家，探测光。这项研究将检查乙酰胆碱（一种微小的化学信使）所通过的受体。受体就像在细胞表面发现的小天线，它们检测环境中的特定化学物质。有许多不同类型的乙酰胆碱受体。每一种都能检测到乙酰胆碱，但对细胞内的分子信号有不同的影响。这项研究将使用模仿或阻断乙酰胆碱的化学物质来找出参与色素分散的受体类型。这项研究将阐明一种新的光适应信号通路，增强对眼睛如何工作的理解。

The proposed research looks at what happens when light hits the eye.Research will examine what happens when the eye adjusts to changing lightlevels and how that information is transmitted between the retina and theretinal pigment epithelium (RPE). It will zero in on tiny chemicalmessengers used by the retina to communicate with the RPE. The RPE is athin layer of tissue located next to the retina.The researchers will use fish eyes as a source of tissue for these studies.Unlike human eyes, fish eyes have pupils of fixed diameter. Fish don'tadjust to changing light by dilating or constricting their pupils the waypeople do. Instead they rearrange their light-sensitive photoreceptors andthe pigment granules in the RPE to get just the right amount of light to thephotoreceptors, rods or cones, best suited for the job. In the light,pigment granules in the RPE spread out into finger-like extensions thatinterlace with the rods and cones. These rearrangements let the RPE shadethe rod photoreceptors, which are specialized for night vision, while stillpermitting the cone photoreceptors, bright light and color visionspecialists, to detect light.This study will examine the receptors through which acetylcholine, one ofthe tiny chemical messengers, operates. Receptors are like little antennaefound on the surface of cells, and they detect specific chemicals in theirenvironment. There are many different types of receptors for acetylcholine.Each detects acetylcholine, but each has a different effect on molecularsignals inside the cell. This study will use chemicals that either mimic orblock acetylcholine to figure out what type of receptor is involved inpigment dispersion. This research will illuminate a novel signaling pathwayfor light adaptation, enhancing understanding of how the eye works.