Flashcards in Exam 2 Koh- Retina Biochem 4 Deck (86)
What is important to RPE function?
Proteins, lipids, and nucleic acids
____% of wet weight of the retina is water
What is the primary carbon source used for energy?
Glucose is not converted to _______ in the RPE
Nearly ______ proteins have been identified in RPE
What gene is RPE specific
______ compose of ~3% of the wet weight of the RPE
______% of wet weight are phospholipids with PC and PE
Higher saturated FAs in the RPE include what?
About 1% of the wet weight of the RPE is contributed by _____
Retinal pigment epithelium is a single layer of cells with what type of junction?
The RPE is a single layer of _____ epithelial cells
Where is the outermost layer of the retina located?
Between the choroid and outer segments
How many RPE cells per eye?
What is the ratio of photoreceptor cells to RPE cells?
Epithelial cells are polarized with long ____ microvillous processes interdigitating the outer segment, and____ aspects adjacent to Bruch's membrane
What serves as a blood-retinal barrier?
Polarized cells in the RPE
What are the retinal pigment epithelium functions?
Light absorption, epithelial transport, glia, visual cycle, phagocytosis, secretion
How does the RPE increase optical quality?
Forming a dark pigmented wall, aids in absorption of scattered light
Blood perfusion of the choriocapillaris is ____ than the kidney
Venous blood from the choriocapillaris shows ___% O2 saturation
By comparison, venous blood from retinal vessels shows a O2 saturation of ____%
What is OCA?
OCA1 and OCA2 are due to defects in what?
The tyrosinase gene and the pink-eyed dilution gene
What happens when melanin levels are below a critical level?
Lack of foveal development, low vision, nystagmus and stabismus
What is the RPEs 3 lines of defense against toxins?
Light absorption, antioxidants and repairment
There is absorption and filtering of light via melanin in ________
There is additional light absorption in the RPE by what 3 things?
Carotenoids, lutein, and zeaxanthin
What does blue light do in the RPE?
Permits the photoxidation of lipofuscin components to cell toxic substances