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Livvyy's Good Looking Science Space







Molecule # 3: Adrenaline


It was the first hormone that was able to be crystallized.
Adrenaline was the beginning of determining some hormonal effects.






Adrenaline
Adrenaline



R = H
Noradrenaline
R = CH3
Adrenaline
Adrenaline is released when the glucose level in the body is low. As a result the rise in blood sugar allows the fermentation of glucose in the muscles. This hormone has a major influence on the on the storage and movement of glycogene and fatty acids.


Adrenaline as a neurotransmitter:
Has an effect on the sympathetic nervous system, which includes the heart, lungs, blood vessels, bladder, gut, etc. It is released by nervous stimulation as a result of physical or mental stress. It binds to a group of transmembrane proteins (adrenergic receptors). There are to kinds: external image moz-screenshot-1.jpgthe external image alpha.gif- and external image beta.gif-receptors.
Its effects are: an increase in the rate and strength of a heartbeat, dilation of pupils, sweating, and a reduced clotting time.



external image moz-screenshot.jpgexternal image hormona.gif















Adrenal Medulla
Adrenal Medulla










L-adrenaline is a hormone and a neurotransmitter. Adrenaline is created in the the neurons of the adrenal medulla.

The synthesis of adrenaline:



external image adrensynthese.gif





Some usages of Adrenaline are:
- oral intake of adrenaline has no effect
-it is used in drugs to support the beating of ones heart
- it is used in drugs for asthma
- to prevent bleeding during surgeries because adrenaline leads to the contraction of blood vessels



Bibliography:


http://www2.ccc.uni-erlangen.de/projects/ChemVis/motm/index.html



Molecule #2:Nitrous Oxide

Nitrous Oxide among many other names, is most commonly known as Laughing Gas, N2O. It is an almost odorless and colorless gas. It was discovered by Joseph Priestley in 1793. The reaction he observed for the creation of of Nitrous oxide was:

2NO + H2O + Fe --> N2O + Fe(OH)


external image n2omol.gif

Nitrous Oxide ^






N2O at room temperature in unreactive with most substances, including alkali metals and halogens. So is it often used a replacement for CFCs that can damage the ozone in aerosol cans. But N2O, when heated, decomposes to N2 and

O2.

external image n2oreact.gif

Humphry Davy later experimented with the physiological properties of gas and its effects upon respiration. He said, "As nitrous oxide in its extensive operation appears capable of destroying physical pain, it may probably be used with advantage during surgical operations in which no great effusion of blood takes place". However for forty years the primary use was for public shows and recreational use.

The possible use of N2O anesthetic was not realized until the 1840's by Dr. Horace Wells. He decided to conduct an experiment where while he was under the effects of Nitrous oxide another local dentist, in Hartford Connecticut would remove one of Wells' molars. The experiment proved the gas as a painkiller when he experienced no pain during the procedure. However in an experiment he conducted in 1845, Wells extracted a tooth from a patient. While the results were slight discomfort instead of excruciating pain they results were not as satisfying to the audience, at the Harvard Medical School in Boston.

Today Nitrous Oxide is still used by dentists as a safe and popular anesthetic, it is mainly used for mild sedation. It is to a degree a painkiller used for dentistry and is less toxic than other alternatives such as chloroform.





Bibliography: Nitrous Oxide- Laughing Gas, Ewan Cameron and Paul May http://www.chm.bris.ac.uk/motm/n2o/n2oh.htm
Brainiac: Does Laughing Gas really work? http://www.youtube.com/watch?v=uZhSGzgu4hk





Molecule #1:Nicotine


Representation of the S molecule in 2D: Representation of the R in 3D:
external image S-nicotine.gif external image S-nicotine2.gif

Nicotine, which is also called 3-(1-methyl-2-pyrrolidinyl)pyridine.

Nicotine posses an asymmetric carbon so it exists in the two above compounds.
In nature Nicotine only exists in the S shape.

Formula
C10H14N2
Molecular Weight
162,234 g.mol-1
Melting point
-7,9 ° C
Boiling point
247 ° C
The absorption of Nicotine depends on pH. When a the pH is acidic or < 7 the Nicotine does not easily pass through membranes.
Surprisingly, the Nicotine in tobacco is acidic for therefore only allows for minimal absorption through the mouth. So Nicotine
needs to be inhaled to be absorbed in larger quantities.
The active form of Nicotine is a cation.

Nicotine rises the stimulation of nicotinic receptors, however he human body over time builds up a tolerance for Nicotine, therefore requiring a greater quantity to have the same pleasurable effect that a smaller quantity previously had. Nicotine causes the production of dopamine, in the brain. Dopamine is a neurotransmitter which is responsible for the "pleasure" effect. Prolonged exposure of these receptors to Nicotine reduces the efficiency of dopamine (it reduces the number of available nicotinic receptors).

Operating cycle of a nicotinic receptor:

external image S-E-recept.gif
Physiological normal conditions: After the opening of the canal by binding to acethylcholine, the receptor becomes desensitized before it goes back to the state of rest or it is regenerated.

external image S-E-recept2.gif
Continuous exposure to tobacco: Nicotine substitutes for acetylcholine and over stimulates the nicotinic receptor. Then, the receptor is long-term inactivated and its regeneration is prevented by nicotine.