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Nicotine is an organic compound, an alkaloid found naturally throughout the tobacco plant, with a high concentration in the leaves. It constitutes 0.3 to 5% of the plant by dry weight. The biosynthesis takes place in the roots and it is accumalated in the leaves. It is a potent nerve poison and is included in many insecticides. In lower concentrations, the substance is a stimulant and is one of the main factors leading to the pleasure and habit-forming qualities of tobacco smoking. In addition to the tobacco plant, nicotine is also found in lower quantities in other members of the Solanaceae (nightshade) family, which includes tomato, potato, eggplant (aubergine), and green pepper. Nicotine alkaloids are also found in the leaves of the coca plant.
The chemical formula of nicotine is C10 Hhydrogen helium H Li Full table General Name, Symbol, NumberHydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1 (IA), 1 , s Density, Hardness 0. 0899 kg/m3, NA Appearance colorless Atomic properties Atomic weight 1. 00794 amu Atomic radius (ca14 NNitrogen is the chemical element in the periodic table that has the symbol N and atomic number 7. A common normally colorless, odorless, tasteless and mostly inert diatomic non-metal gas, nitrogen constitutes 78 percent of Earth's atmosphere and is a cons2.
This structure is reflected in the IUPACThe International Union of Pure and Applied Chemistry IUPAC is an international non-governmental organization devoted to the advancement of chemistry. It has as its members national chemistry societies. It is the recognized authority in developing standar name 3-(2-(N- methylIn chemistry a methyl-group is a hydrophobic Alkyl functional group which is derived from methane (CH). It has the formula C H It is very often abbreviated: :-Me This hydrocarbon unit can be found in many organic compounds, like biodiesel (methyl ester). pyrrolidinyl )) pyridinePyridine is one of the simplest heterocyclic aromatic molecules, with the Hill system formula C H N. Pyridine is structurally similar to benzene, with a single nitrogen atom substituting in the six-member aromatic ring for one of the carbon and one of the.
Nicotine is waterThis article describes water from a scientific and technical perspective. See the water article for its importance for life and mankind. Water is liquid at standard temperature and pressure. It has the chemical formula H O, meaning that one molecule of wa soluble and can be extracted by leaving the cut tobacco in a glass of water for 12 hours.
The CAS number of nicotine is 54-11-5.
In small doses nicotine has a stimulating effect, increasing activity, alertness and memory. Repeat users report a pleasant relaxing effect. It also increases the heartThis page is about the muscular organ, the Heart . For other meanings of the word, see Heart (disambiguation). The heart ( Latin cor is a hollow, muscular organ that pumps blood through the blood vessels by repeated, rhythmic contractions. The term cardia rate and blood pressure and reduces the appetite. In large doses it may cause vomiting and nausea. The LD50 is 50 mg/kg for rats and 3 mg/kg for mice.
Repeat users of nicotine often develop a physical dependency to the chemical. A report released on May 16, 1988 by United States Surgeon General C. Everett Koop stated that the addictive properties of nicotine are similar to those of heroin and cocaine; although many people do not agree with such a comparison. Withdrawal symptoms include irritability, headaches and anxiety. These symptoms may last for months or years, although they peak at around 48-72 hours.
Although the amount of nicotine inhaled with tobacco smoke is quite small (most of the substance is destroyed by the heat) it is still sufficient to cause dependence. The amount of nicotine absorbed by the body from smoking depends on many factors, including the type of tobacco, whether the smoke is inhaled, and whether a filter is used.
As nicotine enters the body, it quickly gets distributed through the bloodstream and can cross the blood-brain barrier. On average it takes about seven seconds for the substance to reach the brain. It acts on the nicotinic acetylcholine receptors. In small concentrations it increases the activity of these receptors, among other things leading to an increased flow of adrenaline, a stimulating hormone. The release of adrenaline causes an increase in heart rate, blood pressure and respiration, as well as higher glucose levels in the blood. Cotinine is a break-down product of nicotine which remains in the blood for up to 48 hours, and so can be used as an indicator of a person's exposure to smoke. In high doses, nicotine blocks the nicotinic acetylcholine receptor, which is the reason for its toxicity and its effectiveness as an insecticide.
In addition, nicotine increases dopamine levels in the reward circuits of the brain. Studies have shown that smoking tobacco inhibits monoamine oxidase (MAO), an enzyme responsible for breaking down monoaminergic neurotransmitters such as dopamine, in the brain. It is currently believed that nicotine by itself does not inhibit the production of monoamine oxidase (MAO), but that other ingredients in inhaled tobacco smoke are believed to be responsible for this activity. Thus it generates feelings of pleasure. This reaction is similar to that caused by cocaine and heroin, and is another reason people keep smoking: to sustain high dopamine levels.
It has been noted that the majority of people diagnosed with schizophrenia smoke tobacco. Estimates for the number of schizophrenics that smoke range from 75% to 90%. It is argued that the increased level of smoking in schizophrenia may be due to a desire to self-medicate with nicotine. [1] [2]
Nicotine and its metabolites are being researched for the treatment of a number of disorders, including ADHD, Parkinson's Disease and Alzheimer's Disease.
It has long been thought that tar and other chemicals in tobacco were the main cause of cancer but recent studies showed that nicotine alone has carcinogenic properties by inhibiting the natural ability of the body to get rid of cells with significant genetic damage before they turn cancerous.
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