Retinal stimulation

Sun H, Molday RS, Nathans J. 1999. Retinal stimulates ATP hydrolysis by purified and reconstituted ABCR, the photoreceptor-specific ATP-binding cassette transporter responsible for Stargardt disease. J Biol Chem 274 8269-8281. 

FIGURE 29.2 Example of an early microfabricated Pt-Ir bipolar electrode for acute preclinical experimentation in retinal stimulation built in 1991 by author (DID) [78]. 

DiLorenzo, D.J., Unpublished Data on Microfabricated Multichannel Electrode Array for Retinal Stimulation, 1991, Massachusetts Institute of Technology. 

Jong-Mo Seoa, Sung June Kimb, Hum Chunga,b, Eui Tae Kimb, Hyeong Gon Yua, Young Suk Yua (2004) Biocompatibility of polyimide microelectrode array for retinal stimulation. Materials Science and Engineering C. 24 185-189. 

Resting potential, in membrane model, 22-2-22-3 Reswick, J., VII-2 Reticular lamina, 5-5 Retina, 4-2-4-3 Retinal ganglion cells, 22-12 Retinal horizontal cells, 22-12 Retinal stimulation, 35-2 Retinitis pigmentosa, sec RP Reul, H 44-3,55-5,55 12 Reynolds, D.V., 29-10 Rho,J.Y.,47-9 Rhode, W.S., 5-4,63-9 Rhythmic electrical activity, in gastrointestinal system, 6-6... 

Stress corrosion cracking, 38-18 Stressed volume, definition, 58-2 Strich, S.J., 52-2 Stride and temporal parameters, in gait analysis, 51-3 Stroke volume (SV), 1-6 Stupp, S.I., 46-10 Sturdivan, L.M., 53-6 Subretinal retinal stimulation, 35-2... 

Vitamin A has an important role in vision in the form of retinal, in which the alcohol group (-OH) is replaced by an aldehyde group (-CHO) by the f-carotene 15,15 -monooxygenase enzyme. As light enters the eye, 1,1,-cis-retinal isomerizes to 1,1-trans-retinal This trans-retinal stimulates a nerve through a series of steps, sending a signal to the visual center of the brain. After the information is sent, the 1,1-trans-retinal will be converted back to 1,1,-cis-retinal for further stimulants. 

The distribution of rods and cones is shown in Figure 3b centered about the fovea, the area of the retina that has the highest concentration of cones with essentially no rods and also has the best resolving capabiUty, with a resolution about one minute of arc. The fovea is nominally taken as a 5° zone, with its central 1° zone designated the foveola. There are about 40 R and 20 G cones for each B cone in the eye as a whole, whereas in the fovea there are almost no B cones. A result of this is that color perception depends on the angle of the cone of light received by the eye. The extremely complex chemistry involved in the stimulation of opsin molecules, such as the rhodopsin of the rods, and the neural connections in the retinal pathway are well covered in Reference 21. 

Fruit juices, meat products, milk and milk products, fish and most vegetables, in which tin is likely to be anodic to steel, can be handled open to the air in tinned steel vessels. Some corrosion of the tin occurs at rates similar to those found for pure tin and in due course retinning may be necessary. The alloy layer in hot-dipped tin coatings is cathodic to both tin and steel and, under aerated conditions may stimulate the corrosion of both metals, but this effect appears to be unimportant in practice. 

Pertussis toxin is produced by the bacterium Bordetella pertussis. It covalently modifies G-proteins of the G/Go family (transfer of a ADP-ribose moiety of NAD onto G-protein a-subunits). ADP-ribosylated G-proteins are arrested in their inactive state and, as a consequence, functionally uncoupled from their respective effectors. Examples for pertussis toxin-sensitive cellular responses include the hormonal inhibition of adenylyl cyclases, stimulation ofK+ channels, inhibition of Ca2+ channels and stimulation ofthe cGMP-phosphodiesterase in retinal rods. 

The above findings are supported in the other studies of the inhibitory effects of flavonoids on iron-stimulated lipid peroxidation. Quercetin was found to be an inhibitor of iron-stimulated hepatic microsomal lipid peroxidation (/50 = 200 pmol I ) [134]. Flavonoids eriodictyol, luteolin, quercetin, and taxifolin inhibited ascorbate and ferrous ion-stimulated MDA formation and oxidative stress (measured by fluorescence of 2,7,-dichlorodihydro-fluorescein) in cultured retinal cells [135]. It should be mentioned that in recent work Heijnen et al. [136] revised the structure activity relationship for the protective effects of flavonoids against lipid peroxidation. 

Klinker IF, Seifert R (1997) Morphine and muscle relaxants are receptor-independent G-protein activators and cromolyn is an inhibitor of stimulated G-protein activity. Inflamm Res 46 46—50 Klinker IF, Seifert R, Datum H, Rommelspacher H (1997) Activation by beta-carbohnes of G-proteins in HL-60 membranes and the bovine retinal G-protein transducin in a receptor-independent manner. Biochem Pharmacol 53 1621-1626... 

A similar enzymatic activity was found in stimulated pulmonar alveolar macrophages from humans guinea pigs and rats and in retinal pigment epithelial cells from chick embryos... 

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