The chemistry of intoxication, or that we don't know about alcohol

To defeat the enemy, you need to know. This also applies to this enemy of our society as drinking. Not enough to convince you that drinking is bad – you also need to explain why. Modern researches of physiologists, biochemists and physicians reveal many important aspects of the mechanism of action of alcohol on the body, allow us to understand the causes of pathological commitment to alcohol.

Alcohol enters the bloodstream
Ethanol due to the small size of the molecules and some physical properties perfectly miscible with water and dissolves well in fats. That is why alcohol is so easily passes through biological membranes: it begins to be absorbed through the mucous membrane in the mouth, and then in the stomach and intestines, and quickly gets into the blood, which spreads throughout the body. But as soon as alcohol enters the body, it begins its decomposition under the action of enzymes, it turns into water and carbon dioxide. The bulk trapped in the body of alcohol (100 mg per hour per kilogram of body weight) is processed in the liver, only 2-5% of it is released in pure form via the kidneys, sweat glands and lungs (exhaled air). The ratio of these two processes – alcohol is consumed in the body and its destruction – depends on the alcohol content in the blood, and hence its intoxicating effect on the brain. Muscle tissue delays the alcohol, and he or it has oxidized (as yet unknown to us ways), or is sent directly to the liver for processing. Otherwise behave fat cells: they accumulate the alcohol, dissolving in fats, and avoids a quick destruction. Therefore, the more muscle mass and less fat tissue in the body, the lower the concentration of alcohol in the blood and the weaker its effect on the brain.

Especially, the alcohol is absorbed if taken on an empty stomach – no food. On the contrary, abundant food, primarily meat, significantly slows down the process of absorption and reduces the alcohol content in the blood by almost half. Apparently, the point here is that the products of digestion, which also enter the bloodstream via the mucous membrane, interfere with the alcohol to be absorbed by competing for the right to pass through the membrane. Much depends on the degree of intoxication and emotional state. On the one hand, negative emotions (grief, depression) seems to accelerate the absorption of alcohol and increase the intoxication. But on the other hand, suction can slow down under the influence of very strong emotions – anger, great joy, etc. On the chemical side of such mental States, we know as yet very little. One can only assume that depression somehow facilitates the passage of alcohol through biological membranes and, possibly, complicates its processing. Strong emotions cause a sharp constriction of blood vessels in the stomach and intestines, passes through them less blood, and the supply of it alcohol naturally slow down.

The rate of absorption of alcohol depends on its concentration in the drinks. The same amount of alcohol in beer (5-6%) or wine (9-20%) effect on the body is much weaker than in the forty-degree vodka: in a large dilution of the alcohol enters the bloodstream more slowly and most of it has time to decay before reaching the brain. But if simultaneously with the alcohol in the stomach into carbon dioxide (Scotch and soda or, say, vodka with beer), it irritates the mucous membrane of the stomach and intestines, the blood flow to it increases, and the rate of absorption of alcohol increases.

Immediate use
Sometimes alcohol is called a stimulant: it seems like it make people feel more lively, more sociable, more energetic. Indeed, a relatively small dose of alcohol stimulates the activity of the body: a slightly increased heart rate, expanded blood vessels of skin and extremities, reduced blood pressure. Disappears as stress, depression. "A shot of vodka before lunch increases the appetite, irritating the mucosa of the stomach and increasing the secretion of gastric juice.

Direct threats to the body such a shot of vodka, of course, does not create. But this momentary "benefit" of alcohol can result in for the body as evil, if the stack becomes a habit. The little man drinks more often, he begins to better tolerate large doses of alcohol, which previously caused him food poisoning. All this eventually leads to severe illness – alcoholism.

Level of intoxication
Alcohol – specific nerve poison. Good dissolving in fats, which is especially rich in the tissue of the brain, it accumulates in the brain in larger quantities than in other organs. The effects of alcohol on the brain depends on its concentration in the blood: as it increase at first and paralyzed the higher centers of the brain are inhibited then the intermediate and finally the lower, in charge of basic vital functions of the body.

In mild intoxication — alcohol concentration in blood is less than 0.05% (the average is equivalent to 100 ml of vodka) — the person relaxes, calms down. With a slightly larger concentration of (0.05%) inhibited the activity of brain centers that control behavior, especially centers of attention and self-control. Starts to affect the stimulating effect of alcohol: a person artificially lifted the mood appears talkativeness, excessive excitement, a little bit lost rational control over their drunken actions and violated the right orientation in reality. With the increasing intoxication with increasing concentration of alcohol in blood to 0.1% (200 ml vodka) – there is intoxication moderate. The centers of her cerebral cortex go into a chaotic excitation of the regulating influence of released underlying subcortical departments, changing the emotional perception (sometimes in such cases speak about "unleashing instincts"). Human behavior in this state is largely dependent on his temperament and personality: some feel anxious, others fall into the causeless gaiety and playfulness, alternating excessive sensitivity with insults and tears, the third appears suspiciousness, irritability and aggressiveness. With an even higher alcohol content in the blood (0,15% – 300 ml of vodka) suppressed the activity of motor centers of the brain – the person begins to lose control of his muscles. And when the alcohol concentration of 0.25—0.3% (400 – 600 ml of vodka) it is a tough drunk – man completely loses his orientation, he feels an uncontrollable desire to sleep falls into unconsciousness.

And at the last turn suppressed the vital centres located in medulla oblongata: when the concentration of blood alcohol of 0.5% (average 1000 ml of vodka) blocked the center of breathing, and the numbness goes into death.



Alcohol and neurotransmitters
The effect of alcohol on the psyche described in hundreds of literary works and clinical studies. However, we still know very little about the specific points of the action of alcohol, it causes changes in the activity of nerve cells, which ultimately boil down these well-known psychic phenomenon.

The fact that our knowledge about the chemistry of normal mental activity and emotions, there are still significant gaps. Only in recent years we start to speak about the complex processes of the human psyche in the language of physiology, anatomy, biochemistry, and even mathematics. The "atom" of our entire nervous system is the nerve cell – the neuron with the ability to conduct nerve impulse – wave of excitation, which is based on complex electrochemical processes. The nerve impulse can be transmitted from one neuron to another, are in contact with him. However, this contact is not direct: "at the intersection" of neurons – the synapse – they are separated by a gap width of about 200 angstroms. Electrical excitation wave cannot cross this gap, therefore, in the transmission of nerve impulses at the synapses involved also a special substances-mediators – mediators.

In that moment, when the nerve impulse arrives at the end of the neuron but one side of the synapse, here from special vesicles inside the neuron highlighted in the molecules of the substance–of the mediator; they "boost" the synaptic gap, penetrate into the neuron lying across the synapse, and drive electrochemical processes leading to the emergence of a nerve impulse. Now "restored" the momentum can continue its movement to the next neuron.

It is only the overall picture of transmission of nerve impulses from one neuron to another, many details we don't know yet. Neurophysiological studies bring new information on the work of nerve cells. For example, recently it became clear that in addition to the synapses through which passes the excitation, there are brake synapses: when it comes to them nerve impulse from another neuron excitability of the neuron is reduced. These synapses are served by special mediators of inhibition, among which great importance is gammaaminobutyric acid (GABA); it is the opposite action of such mediators in the initiation as epinephrine, norepinephrine, acetylcholine.

What effect on the whole this complicated mechanism of alcohol?
Now there is a growing body of evidence that it directly affects the metabolism of neurotransmitters. For example, occur under the action of relatively small doses of alcohol the state of arousal associated with the release into the tissues of the brain mediator of excitation – adrenaline. For more severe intoxication decreases the content of the neurotransmitters norepinephrine and serotonin – this appears to be due to appearing "drunk" complacent mood. Further increase in the concentration of alcohol in the blood contributes to accumulation of serotonin, which causes depression. In acute alcohol poisoning in the brain of experimental animals was discovered sharply increased content of GABA neurotransmitter of inhibition. Perhaps this is due to the development of so-called protective inhibition: turn off of nerve cells in the cerebral cortex and confluence them into a state of deep sleep can to a certain extent to protect them from the harmful effects of alcohol.

However, we still do not know why and how alcohol causes such changes in the metabolism of neurotransmitters. Apparently, the molecules of alcohol can interact with the so-called macroergic compounds, which serve as a source of energy for all intracellular processes, including those involved in the transmission of nerve impulses. Alcohol may also contact the enzyme adenosinetriphosphatase, whereby the decomposition of macroergic compounds with release of energy. But this is only the most General assumptions – full picture of the process it is unclear to us.

And about the metabolism of normal nerve cell we have pretty poor data. Suffice it to say that an important role of some chemical factors in the activity of brain cells was first discovered it when observing the changes occurring under the influence of alcohol. And almost entirely unexplored intermediate stage of a complex process, one end of which the changes of trace amounts of neurotransmitters, and the other violations of the human psyche, the changes in his moods and behavior in General.

Why have a hangover?
The effect of alcohol is evident not only at the molecular level, at the level of biochemical and electrochemical processes occurring in the nerve cell and the synapse. Neurophysiological studies indicate that under the influence of alcohol happen and other violations of the functioning of the body and primarily the brain.

The brain to a greater extent than any other tissue, needs stable n abundant supply of oxygen. Alcoholic intoxication reduces the intensity of circulation and respiration in the brain. Most likely, under the influence of alcohol dissolved the capillaries of the brain: experiments have shown that a drunk person in the brain occurs a large number of small hemorrhages and an even greater number of vessels sealed. This deprives the nerve cells of food and oxygen. Under normal conditions, oxygen starvation of the nerve cells manifests itself in General weakness, decreased ability to concentrate, headaches. In this condition the nerve cells, and, possibly, poisoning the brain decay products those who have died, unable to withstand the lack of oxygen, due, apparently, known for the morning hangover with headache, fatigue, etc. (we are not talking here about the "hangover" – an irresistible thirst for alcohol, characterized by chronic alcoholics; there are other mechanisms).

There is no doubt that such severe trials that befell the nerve cells in the brain, lead to premature wear, accompanied by violations of higher nervous activity. However, the human brain contains billions of nerve cells, and if from time to time even destroyed several thousand of them, it does not lead to significant changes. But because the nerve cells in contrast to all other not capable of regeneration. But if a person regularly drinks over the years, that eventually the accumulation of these small changes lead to very serious consequences.

Facts for a snack

Anesthesia, rolling in paralysis
Alcohol is a drug. Like other drugs in its effect on the nervous system one can distinguish three successive stages: excitation, anesthesia, paralysis. But unlike most drugs used in medicine, alcohol is the interval between the stages of anesthesia and the stage of paralysis at high doses is very short. That is why ethanol is not widely used for surgical anesthesia: he has, as doctors say, too small therapeutic range. In other words, the alcohol concentration, which causes paralysis, but not much more than the required length of anesthesia, and this means that even a small overdose is dangerous.

But why you two?
There are many jokes and anecdotes about alcoholic diplopia is "double vision". This phenomenon can be observed and sober. If looking at the subject, to shift the finger pressure one eye, the visible image of the object will immediately be doubled. This is because the visual axis is shifted and the image falls on the asymmetric locations of the retina of both eyes. The visual axis can shift and due to the temporary dysfunction of the eye muscles that occurs as a result of drinking alcohol, especially strong drinks with a high content of fusel oils (vodka, chacha, etc.). The toxic effect of alcohol creates the oculomotor centre of the brain lesion inhibition, the muscles of the eye are reduced weaker, and the person begins to "go blind".

First the first and then the "fast"
Acute alcohol poisoning is dangerous for life. If the person is still conscious, the main task of first aid is to act on the respiratory center. For this purpose a piece of cotton wool moistened with liquid ammonia and from time to time give to inhale the fumes. To facilitate poisoned we need to get him to drink at least five glasses of boiled water at room temperature, adding each in two tablespoons of baking soda for better removal of mucus. Then induce vomiting by pushing a shard of the spoon on the tongue, give to drink hot tea or coffee. If intoxicated with alcohol, lost consciousness, it is necessary to call "ambulance". Before the arrival of the doctor it is necessary to put the unconscious on his side with his head down (this prevents the ingress of mucus and vomit in the windpipe). The language should be output to warn him ceasing in his throat.

Source: "Chemistry and life", 1974

P. S. And remember, only by changing their consumption — together we change the world! ©

Source: http://Science-Fact"

Tags

See also

New and interesting