An ultrastructural study of the frog retinal rod photoreceptor membranes phagocyted by pigment epithelium cells after aldehyde fixations and organic solvents treatments

1973 ◽  
Vol 13 (4) ◽  
pp. 753-VIII ◽  
Author(s):  
V.L. Borovjagin ◽  
T.A. Ivanina
Keyword(s):  
Organic Solvents ◽  
Ultrastructural Study ◽  
Pigment Epithelium ◽  
Rod Photoreceptor ◽  
Retinal Rod ◽  
Epithelium Cells ◽  
Photoreceptor Membranes

scholarly journals THE ULTRASTRUCTURE OF LIPID-DEPLETED ROD PHOTORECEPTOR MEMBRANES

1974 ◽  
Vol 63 (2) ◽  
pp. 587-598 ◽  
Author(s):  
Izhak Nir ◽  
Michael O. Hall
Keyword(s):  
Lipid Extraction ◽  
Fatty Acid Analysis ◽  
Major Protein ◽  
Rod Photoreceptor ◽  
Thin Sections ◽  
Retinal Rod ◽  
Layer Chromatography ◽  
Chloroform Methanol ◽  
Photoreceptor Membranes

The structure of lipid-depleted retinal rod photoreceptor membranes was studied by means of electron microscopy. Aldehyde-fixed retinas were exhaustively extracted with acetone, chloroform-methanol, and acidified chloroform-methanol. The effect of prefixation on the extractability of lipids was evaluated by means of thin-layer chromatography and fatty acid analysis. Prefixation with glutaraldehyde rendered 38% of the phospholipids unextractable, while only 7% were unextractable after formaldehyde fixation. Embedding the retina in a lipid-retaining, polymerizable glutaraldehyde-urea mixture allows a comparison of the interaction of OsO4 with lipid-depleted membranes and rod disk membranes which contain all their lipids. A decrease in electron density and a deterioration of membrane fine structure in lipid-depleted tissue are correlated with the extent of lipid extraction. These observations are indicative of the role of the lipid bilayer in the ultrastructural visualization of membrane structure with OsO4. Negatively stained thin sections of extracted tissue reveal substructures in the lipid-depleted rod membranes. These substructures are probably the opsin molecules which are the major protein component of retinal rod photoreceptor membranes.

scholarly journals Sensitive light scattering probe of enzymatic processes in retinal rod photoreceptor membranes

1984 ◽  
Vol 81 (3) ◽  
pp. 743-747 ◽  
Author(s):  
J. W. Lewis ◽  
J. L. Miller ◽  
J. Mendel-Hartvig ◽  
L. E. Schaechter ◽  
D. S. Kliger ◽  
...  
Keyword(s):  
Light Scattering ◽  
Rod Photoreceptor ◽  
Retinal Rod ◽  
Photoreceptor Membranes

scholarly journals The Ingenious Interactions Between Macrophages and Functionally Plastic Retinal Pigment Epithelium Cells

2016 ◽  
Vol 57 (14) ◽  
pp. 5945 ◽  
Author(s):  
Takahiro Yamawaki ◽  
Eiko Ito ◽  
Atsushi Mukai ◽  
Morio Ueno ◽  
Jun Yamada ◽  
...  
Keyword(s):  
Retinal Pigment Epithelium ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Retinal Pigment Epithelium Cells ◽  
Epithelium Cells

scholarly journals Voltage-Dependent Calcium Channel CaV1.3 Subunits Regulate the Light Peak of the Electroretinogram

2007 ◽  
Vol 97 (5) ◽  
pp. 3731-3735 ◽  
Author(s):  
Jiang Wu ◽  
Alan D. Marmorstein ◽  
Jörg Striessnig ◽  
Neal S. Peachey
Keyword(s):  
Calcium Channel ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Rod Photoreceptor ◽  
Wild Type ◽  
Fast Oscillation ◽  
Light Peak ◽  
Voltage Dependent Calcium Channel ◽  
Voltage Dependent ◽  
Voltage Dependent Calcium Channels

In response to light, the mouse retinal pigment epithelium (RPE) generates a series of slow changes in potential that are referred to as the c-wave, fast oscillation (FO), and light peak (LP) of the electroretinogram (ERG). The LP is generated by a depolarization of the basolateral RPE plasma membrane by the activation of a calcium-sensitive chloride conductance. We have previously shown that the LP is reduced in both mice and rats by nimodipine, which blocks voltage-dependent calcium channels (VDCCs) and is abnormal in lethargic mice, carrying a null mutation in the calcium channel β4 subunit. To define the α1 subunit involved in this process, we examined mice lacking CaV1.3. In comparison with wild-type (WT) control littermates, LPs were reduced in CaV1.3−/− mice. This pattern matched closely with that previously noted in lethargic mice, confirming a role for VDCCs in regulating the signaling pathway that culminates in LP generation. These abnormalities do not reflect a defect in rod photoreceptor activity, which provides the input to the RPE to generate the c-wave, FO, and LP, because ERG a-waves were comparable in WT and CaV1.3−/− littermates. Our results identify CaV1.3 as the principal pore-forming subunit of VDCCs involved in stimulating the ERG LP.

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