Ultrastructural Changes of Smoooth Endoplasmic Reticulum in the Retinal Pigment Epithelium by Choline Chloride

The pigment epithelium is located between the choriocapillary and the visual cells. The pigment epithelial cell is characterized by a large amount of the smooth endoplasmic reticulum (SER) in its cytoplasm. In addition, the pigment epithelial cell of some lower vertebrate has myeloid body as a specialized form of the SER. Generally, SER is supposed to work in the lipid metabolism. However, the functions of abundant SER and myeloid body in the pigment epithelial cell are still in question. This paper reports an attempt, to depict the functions of these organelles in the frog retina by administering one of phospholipid precursors.

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Characterization of artificially re-pigmented ARPE-19 retinal pigment epithelial cell model

Scientific Reports ◽

10.1038/s41598-019-50324-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 10

Author(s):

Laura Hellinen ◽

Marja Hagström ◽

Heidi Knuutila ◽

Marika Ruponen ◽

Arto Urtti ◽

...

Keyword(s):

Retinal Pigment Epithelium ◽

Epithelial Cell ◽

Cell Line ◽

Retinal Pigment Epithelial ◽

Cell Model ◽

Retinal Pigment Epithelial Cell ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Retinal Pigment Epithelial Cells ◽

Pigment Epithelial

Abstract Melanin pigment has a significant role in ocular pharmacokinetics, because many drugs bind at high extent to melanin in the retinal pigment epithelial cells. Most retinal pigment epithelial cell lines lack pigmentation and, therefore, we re-pigmented human ARPE-19 cells to generate a pigmented cell model. Melanosomes from porcine retinal pigment epithelium were isolated and co-incubated with ARPE-19 cells that spontaneously phagocytosed the melanosomes. Internalized melanosomes were functionally integrated to the cellular system as evidenced by correct translocation of cellular Rab27a protein to the melanosomal membranes. The pigmentation was retained during cell cultivation and the level of pigmentation can be controlled by altering the amount of administered melanosomes. We used these cells to study melanosomal uptake of six drugs. The uptake was negligible with low melanin-binders (methotrexate, diclofenac) whereas most of the high melanin-binders (propranolol, chloroquine) were extensively taken up by the melanosomes. This cell line can be used to model pigmentation of the retinal pigment epithelium, while maintaining the beneficial cell line characteristics, such as fast generation of cultures, low cost, long-term maintenance and good reproducibility. The model enables studies at normal and decreased levels of pigmentation to model different retinal conditions.

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Fine Structure of the Retinal Pigment Epithelium, Bruch's Membrane, and Choriocapillaris in the Northern Pike (Esox lucius)

Journal of the Fisheries Research Board of Canada ◽

10.1139/f74-202 ◽

1974 ◽

Vol 31 (10) ◽

pp. 1601-1605 ◽

Cited By ~ 7

Author(s):

C. R. Braekevelt

Keyword(s):

Endoplasmic Reticulum ◽

Fine Structure ◽

Retinal Pigment Epithelium ◽

Epithelial Cell ◽

Basal Lamina ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Northern Pike ◽

Bruch's Membrane ◽

Bruch’S Membrane

The fine structure of the retinal pigment epithelium, Bruch's membrane, and the choriocapillaris has been studied by light and electron microscopy in the adult northern pike (Esox lucius).The pigment epithelium is composed of a single layer of large cells. Each epithelial cell has abundant mitochondria, smooth endoplasmic reticulum, myeloid bodies, phagosomes, and pigment granules. Rough endoplasmic reticulum and ribosomes are scarce.The scleral or basal border of the epithelial cell is not infolded whereas the vitreal or apical surface displays numerous, fine, elongated processes which surround the inner and outer segments of the photoreceptors.Bruch's membrane is composed of three layers. The innermost layer is the basal lamina of the pigment epithelium. The outermost layer is the basal lamina of the choriocapillaris endothelium. Between these basal laminae is a layer of fine fibrils. The overall thickness of Bruch's membrane is 3.5–4 μ posteriorly.The endothelial wall of the choriocapillaris bordering Bruch's membrane is typically very thin but nonfenestrated. Vesicles are common in the endothelial cytoplasm.This region of the pike eye differs morphologically from that described for most other vertebrates.

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Dynamics of ultrastructural changes in the chorioretinal complex of rat eyes induced by high dose of methanol

Bulletin of Taras Shevchenko National University of Kyiv Series Biology ◽

10.17721/1728_2748.2016.71.36-40 ◽

2016 ◽

Vol 71 (1) ◽

pp. 36-40

Author(s):

N. Molchanyuk

Keyword(s):

Smooth Endoplasmic Reticulum ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Photoreceptor Cells ◽

Ultrastructural Changes ◽

High Dose ◽

Regenerative Processes ◽

Retinal Photoreceptor ◽

Local Destruction ◽

Destructive Processes

The structure of chorioretinal complex (CRC) of rat eyes was studied by electron microscopy: choriocapillaris, retinal pigment epithelium (RPE) and retinal photoreceptor cells after 40 minutes, 1 hour and 10 minutes, on the first 1 st , 3 rd , 7 th and 14 th days after a single intraperitoneal injection of methanol in a dose of 7.0 g/kg of body weight. It was shown that the primary and significant destructive changes in the structures of the studied complex were observed in the RPE cells, which are characterized by alteration of mitochondria and tubules of smooth endoplasmic reticulum, equation of basal folds and local destruction of the apical microvilli. The destructive processes in the cells were growing in the dynamics of CRC structures research. In parallel, the features of compensatory-regenerative processes in these cells were detected.

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Fine structure of the retinal pigment epithelium in the mud minnow (Umbra limi)

Canadian Journal of Zoology ◽

10.1139/z80-031 ◽

1980 ◽

Vol 58 (2) ◽

pp. 258-265 ◽

Cited By ~ 8

Author(s):

C. R. Braekevelt

Keyword(s):

Endoplasmic Reticulum ◽

Fine Structure ◽

Epithelial Cells ◽

Smooth Endoplasmic Reticulum ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Apical Surface ◽

Phagocytic Cells ◽

Bruch's Membrane ◽

Bruch’S Membrane

The fine structure of the retinal pigment epithelial layer and associated regions has been studied by electron microscopy in the adult mud minnow Umbra limi. The pigment epithelium is composed of a single layer of large columnar cells. Each epithelial cell has abundant small mitochondria, much smooth endoplasmic reticulum (often in highly organized arrays), myeloid bodies, phagosomes and pigment granules. Rough endoplasmic reticulum and ribosomes are scarce. The scleral or basal border of the epithelial cells is but minimally infolded whereas the vitreal or apical surface displays numerous elongated processes which surround the inner and outer segments of the photoreceptors. Unattached, presumably phagocytic cells are a constant feature both between the retinal epithelial cells and within Bruch's membrane. Bruch's membrane lacks a central elastic layer and is composed only of three layers. The endothelial wall of the choriocapillaris bordering Bruch's membrane is typically very thin with a few fenestrations. This region of the mud minnow eye is morphologically similar to that described in other teleost species but differs from that described in most mammals.

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