It:Retinal
Retinal, also known as retinaldehyde or retinene1 is the most important molecule associated with vision. Retinal changes structure when it is exposed to light, essentially transferring the energy from the light it absorbs to an electrical impulse in the retina of the eye, which is then passed along the optic nerve to the central nervous system to be processed. All vision systems operate in this manner, so Retinal is resposible for all vision. Retinal is a retinine molecule that exists as two different isomers - 11-cis retinal and all-trans retinal.
Structure of Cis-Retinal
| 2D Structure | 3D Structure | ||
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Properties of Cis-Retinal and Trans-Retinal
| Properties of Cis-Retinal | Properties of Trans-Retinal | |
| General properties | ||
| Chemical name | (11Z)-retinal | ... |
| Chemical formula | C20H28O | C20H28O |
| Molecular mass | 284 g/mol | 284 g/mol |
| Physical properties | ||
| Melting point | ... °C | ... °C |
| Boiling point | ... °C | ... °C |
| Appearance | ... | ... |
| Miscelleneous | ||
| SMILES | CC1(C)C(/C=C/C(C)=C/C=C\C(C)=C\C=O)
=C(C)CCC1 |
CC1(C)C(/C=C/C(C)=C/C=C/C(C)=C/C=O)
=C(C)CCC1 |
Structure of all-trans retinal
| 2D Structure | 3D Structure | ||
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| ChemDraw 3D structure | |||
The role of retinal in the vision process
The molecule that takes part in the vision process is rhodopsin which consists of 11-cis retinal and protein opsin. Retinal is a Vitamin A derivative. When there is no light present the 11-cis retinal has a bent configuration and is attached to the retinal molecule in a stable arrangement. When light strikes the retina, the retinal molecule absorbs a photon into one of the pi-bonds between the 11th and 12th carbon atoms, hence the 11 cis retinal is transfformed into the all trans retinal.
| Structure A | Structure B | ||||
Synthesis of Rhodopsin
Effects of Bunazosin on ocular circulation and retinal neuronal damage
By applying bunazosin hydrochloride into a healthy humans, it increases the blood velocity in the optic nerve head(ONH),retina and choroid, without changing either heart rate and blood pressure dramaticallt. This drug was also applied to rabbits and rats, giving positive results. These shows that bunazosin hydrochloride have improvement effect both in the ocular circulation and a direct neuroprotective effct. Therefore, it may be useful to use bunazosin hydrochloride as a therapeutic drug against retinal diseases which is associated with the ocular circulation.
References
- Beilstein Data: Copyright (c) 1988-2006, Beilstein institut zur Foerderung der Chemischen Wissenschaften licensed to Beilstein GmBH and MDL information systems GmbH
- 1.Chang, Raymond (1998). Chemistry, 6th Ed.. New York: McGraw Hill. ISBN 0-07-115221-0.
- 2. Feynman, Richard (1985). QED - The Strange Theory of Light and Matter. Princeton, New Jersey: Princeton University Press. ISBN 0691024170.
- 3.Hara, Hideaki / Ichikawa, Masaki / Oku, Hidehiro / Shimazawa, Masamitsu / Araie, Makoto, Cardiovascular drug reviews, Apr 2005