NOT. Introduced In 1902, she showed that the nerve site, exposed to alteration - poisoning or damage, acquires low lability. This means that the state of excitement that occurs in this area disappears slower than in the normal area. Therefore, at a certain stage of poisoning under action on the overlying normal portion, the poisoned area is not able to reproduce this rhythm, and the excitation is not transmitted through it. Such a state of reduced lability N.E.Vedhensky called parabito (From the word "Para" - about and "Bios" - life) to emphasize that normal life activity is broken in the parabiasis site.
Parabiosis - This is a reversible change, passing in the deepening and strengthening of the action of the agent that caused its agent into an irreversible violation of life - death.
Classic experiments N. E. Vvedensky were carried out on a neuromuscular frog preparation. The nerve studied in a small area was subjected to alteration, i.e. caused a change in its condition under the influence of an application of any chemical agent - cocaine, chloroform, phenol, potassium chloride, strong pharadic current, mechanical damage, etc. The irritation was applied either to Plot of nerve or above it, i.e., so that the pulses arose in the parabiotic site or passed through it in their path to the muscle. On the conduct of excitement on the nero N. E. Vvedensky tried to reduce the muscles.
In a normal nerve, an increase in the strength of rhythmic irritation of the nerve leads to an increase in the forces of the Tetanic abbreviation ( fig. 160, A.). In the development of parabells, these relationships are naturally changed, and the following stages consistently replacing each other are observed.
- Provisorial, or equalizing, phase. In this initial phase of alteration, the ability of the nerve to carry out rhythmic pulses decreases with any power of irritation. However, as introduced by the introduction, the decrease is sharply affected by the effects of stronger irritations, the more moderate: as a result of this, the effects of those and others are almost initiating ( fig. 160, B.).
- Paradoxical phaseit follows the equalization and is the most characteristic phase of parabitimate. According to N. E. Vvedensky, it is characterized by the fact that strong excitations emerging from normal nerve points are not transmitted to the muscle through a narcotized area or cause only initial abbreviations, while the excitation is very moderately capable of causing quite significant tetanic cuts ( fig. 160, B.).
- Thoring phase- The last stage of parabiosis. During this period, the nerve completely loses the ability to initiate any intensity.
The dependence of the effects of nerve irritation from the current force is due to the fact that with increasing the strength of the stimulus, the number of excited nerve fibers increases and the frequency of pulses arising in each fiber increases, since the strong stimulus is able to cause the pulse volley.
Thus, the nerve reacts a high frequency of excitations in response to strong irritation. When developing parabiasis, the ability to reproduce frequent rhythms, i.e. lability, falls. This leads to the development of the phenomena described above.
With a small force or rare irritation rhythm, each impulse arising in the intact nerve section is carried out through a parabiotic portion, since by the time it came into this area the excitability reduced after the previous pulse fully time to recover.
With strong irritation, when the impulses follow each other with a high frequency, each next pulse coming into the parabiotic portion falls into the stage of relative refractoriness after the previous one. In this stage, the excitability of the fiber is sharply reduced, and the amplitude of the response is reduced. Therefore, the propagating excitation does not occur, but only an even greater decrease in excitability occurs.
In the parabios section, the impulses are quickly coming by each other as themselves block the path. In the equalization phase of parabiosis, all these phenomena are still weakly expressed, therefore only the transformation of frequent rhythm is happening into more rare. As a result, the effects of frequent (strong) and relatively rare (moderate) irritation is equalized by the paradoxical stage of excitability recovery cycles so dragged so much that frequent (strong) irritations are at all ineffective.
With particularly clarity, these phenomena can be traced on single nerve fibers when irritating them in incentives of different frequency. So, I.Tasaki affected one of the interceptions of the injury of myelin nerve fiber frogs with a solution of urethane and investigated through such interception of nerve impulses. He showed that, while rare incentives passed through the interception unhindered, frequent detained them.
N. E. Vvedensky considered parabitosis as a special state of persistent, uncolving excitation, as if frozen in one section of the nerve fiber. He believed that the excitation waves arriving in this section from the normal parts of the nerve, as if summed up with the "stationary" excitation existing here and deepen it. Such a phenomenon of N. E. Vvedensky considered as a model of transition of excitation to braking in nervous centers. Brake, according to N. E. Vednited, is the result of "over-excitation" of the nervous fiber or nervous cell.
Parabiosis (in Per.: "Para" - about, "bio" - life) - this is a condition on the verge of life and death of the fabric, which occurs when exposed to toxic substances such as drugs, phenol, formalin, various alcohols, alkalis and others, and Also a long effect of electric current. The doctrine of parabital is associated with the clarification of braking mechanisms, which underlies the life of the body (I. P. Pavlov this problem called the "damned issue of physiology").
Parabites develops in pathological conditions, when the lability of the central nervous system structures decreases or a very massive simultaneous excitation of a large number of afferent paths, such as, for example, with traumatic shock.
The concept of parabital in physiology was introduced by Nikolai Evgenievich Vvedensky. In 1901, his monograph "Excitation, braking and anesthesia" was published, in which the author on the basis of his research suggested the unity of the initiation and braking processes.
N. E. Vvedensky in 1902 showed that the site of the nerve, subjected to alteration - poisoning or damage, acquires low lability. Such a state of reduced lability of N.E. The introduced was called parabital (from the word "Para" - about and "bios" - life) to emphasize that normal life activity is broken in the parabiasis site.
N. E. Vvedensky considered parabitosis as a special state of persistent, uncolving excitation, as if frozen in one section of the nerve fiber. He believed that the excitation waves arriving in this section from the normal parts of the nerve, as if summed up with the "stationary" excitation existing here and deepen it. Such a phenomenon of N. E. Vvedensky considered as a model of transition of excitation to braking in nervous centers. Brake, according to N. E. Vednited, is the result of "over-excitation" of the nervous fiber or nervous cell.
Parabiosis - This is a reversible change, passing in the deepening and strengthening of the action of the agent that caused its agent into an irreversible violation of life - death.
Classic experiments N. E. Vvedensky were carried out on a neuromuscular frog preparation. The studied nerve on the small site was subjected to alteration, i.e. caused a change in its condition under the influence of the application of a chemical agent - cocaine, chloroform, phenol, potassium chloride, strong pharadic current, mechanical damage, etc. The irritation was applied either by the poisoned section of the nerve or above it, so that the pulses arose in the parabital area or passed through it on their way to the muscle. On the conduct of excitement on the nero N. E. Vvedensky tried to reduce the muscles.
In a normal neuromuscular drug, an increase in the strength of rhythmic nerve irritation leads to an increase in muscle contraction force. In the development of parabells, these relationships are naturally changing.
The following parabiasis stages are observed:
1. Equal, or pile, phase. This parabiosity stage is preceded by the rest, hence its name - piercing. It is called it because during this period of development of the parabiotic state of the muscle corresponds to the same abbreviations on strengths and weak irritations applied to the nerve area located above the an alterated area. In the first step of parabiasis, there is a transformation (alteration, translation) of frequent excitation rhythms into more rare. However, as introduced by the introduction, the decrease is sharply affecting the effects of stronger irritation, the more moderate: as a result, the effects of those and others are almost equal.
2. The paradoxical phase follows the equalization and is the most characteristic phase of parabiosis. This stage occurs as a result of continuing and deepening changes in the functional properties of the parabiotic segment of the nerve. According to N. E. Vvedensky, it is characterized by the fact that strong excitations coming out of normal points of the nerve are not transmitted to the muscle through a narcotic plot or cause only initial reductions, while the excitation is very moderately able to cause quite significant muscle contractions.
Fig. 2. Paradoxical stage of parabitease. Nervo-muscular frog preparation with developing parabias after 43 minutes after lubricating the nerve area cocaine. Strong irritations (at 23 and 20 cm. The distance between the coils) give rapidly passing abbreviations, while weak irritations (at 28, 29 and 30 cm) continue to cause long-term reductions (according to N. E. Vvedensky)
3. Thoring phase - the last parabiosis stage. A characteristic feature of this stage is that in the parabiotic portion of the nerve, excitability and lability are not only sharply reduced, but it also loses the ability to carry out the muscle and weak (rare) excitation waves.
Many physiological states of humans and animals, such as the development of sleep, hypnotic states can be explained from parabiosis positions. In addition, the functional value of parabiasis is determined by the mechanism of action of some medicines. So, at the heart of the dual, local anasthetics (Novocaine, Lidocaine, etc.), analgesics, inhalation of the anesthesia lies this phenomenon.
Local anesthetics (from Greek. An - denial, Aesthesis - sensitivity) reversibly reduce the excitability of sensitive nerve endings and block the conduction of the pulse in the nerve conductors at the place of direct use. These substances are used to eliminate pain. For the first time, the drug from this group of Cocaine was highlighted in 1860 by Albert Niman from the leaves of the South American Shrub Erythroxylon Coca. In 1879 V.K. AREPEMSTOR Military Medical Academy of St. Petersburg confirmed the ability of cocaine to cause anesthesia. In 1905, E. Eindhorn synthesized and applied Novocain for local anesthesia. Since 1948, Lidocaine is used.
Local anesthetics consist of hydrophilic and lipophilic parts, which are connected by ether or alkyd bonds. Biologically (physiologically) the active part is the lipophilic structure, forming an aromatic ring.
The mechanism of the action of local anesthetics is a violation of the permeability of the rapid potential-dependent sodium channels. These substances are associated with open sodium channels during the action potential and cause them to inactivation. Local anesthetics do not interact with closed channels during rest potential and channels in an inactivated state, during the development of the phase of repolarization of the potential of action.
Receptors for local anesthetics are located in S 6 segment of the IV domain of the intracellular part of sodium channels. In this case, the action of local anesthetics reduce the permeability of activated sodium channels. This in turn causes an increase in the arousal threshold, and ultimately, to a decrease in tissue excitability. At the same time, there is a decrease in the number of potentials of action and the rate of excitation. As a result, a block for nerve impulses is formed in the field of application of local anesthetics.
According to one of the theories, the mechanism of action for inhalation of drugs is also described from the standpoint of the theory of parabiosis. NOT. The introduction believed that the means for inhalation of anesthesia act on the nervous system as severe irritants, causing parabiteances. At the same time, there is a change in the physicochemical properties of the membrane and the change in the activity of ion channels. All these processes cause the development of parabiasis with a decrease in lability, conductivity of neurons and the central nervous system as a whole.
Currently, the term parabital is used in particular to describe pathological and extreme states.
An example of a pathological state are experimental neurosis. They develop as a result of overvoltage in the cerebral cortex of basic nerve processes - excitation and braking, their strength and mobility. Neuroses with a repeated overvoltage of higher nervous activity can occur not only acutely, but also chronically for many months or years.
The neurosis is characterized by a violation of the main properties of the nervous system, normalizing the processes of irritation and excitation determining the relationship. As a result, weakening of the health of nerve cells can be observed, violation of equilibrium, etc. In addition, phase states are characterized for neuroses. Their entity lies in the disorder between the action of the irritant and the response.
Phase phenomena may occur not only in pathological conditions, but also very briefly, for several minutes, when moving from wakefulness to sleep. In neurosis, the following phases are distinguished:
Equability
In this phase, all conditional stimuli, regardless of their strength, give the same answer.
Paradoxical
In this case, weak stimuli give a strong effect, and the strong - the smallest effect.
Ultraparadsal
Phase, when positive stimuli begins to act as negative, and vice versa, i.e. The reaction of the cortex of the brain on the action of irritants occurs.
Brake
It is characterized by the weakening or complete disappearance of all conditional reflector reactions.
However, it is not always possible to observe a strict sequence in the development of phase phenomena. Phase phenomena with neurosis coincide with phases, previously open N.E. Introduced on the nervous fiber when switching it to a parabiotic state.
Causes of parabitony
These are a variety of damaging effects on an excitable tissue or a cell that do not lead to gross structural changes, but in one way or another violates its functional state. Such reasons may be mechanical, thermal, chemical and other stimuli.
Parabiosis phenomenon essence
As the introduced itself considered, the parabitony is based on the decrease in excitability and conductivity associated with sodium inactivation. Soviet cytoophysiologist N.A. Petroshin believed that the parabiasis was based on reversible changes in protoplasm proteins. Under the action of a damaging agent cell (tissue), without losing structural integrity, completely stops functioning. This condition develops phase, as the damage to the damaging factor (that is, it depends on the duration and strength of the current stimulus). If the damaging agent does not remove in time, then the biological death of the cell (tissue) comes. If this agent is removed on time, then the fabric is also returned to a normal state.
Experiments N.E. Introduced
Vvedensky conducted experiments on the neuromuscular frog preparation. On the sciatic nerve of the neuromuscular drug, testing irritants of different power were consistently applied. One stimulus was a weak (threshold), that is, caused the minimum largest reduction in the icy muscle. Another stimulus was strong (maximum), that is, the smallest of those that cause the maximum reduction of the icy muscle. Then the damaging agent was applied to the nerve at the nerve and every few minutes of the neuromuscular drug was tested: alternately weak and strong stimuli. At the same time, the following stages were sequentially developed:
- Equabilitywhen, in response to a weak stimulus, the magnitude of the abbreviation of the muscle did not change, and in response to a strong amplitude of the muscle contraction, decreased sharply and became the same as when responding to a weak stimulus;
- Paradoxicalwhen, in response to a weak stimulus, the magnitude of the abbreviation of the muscle remained the same, and in response to a strong stimulus, the amount of the reduction amplitude became less than in response to a weak stimulus, or the muscle did not decrease at all;
- BrakeWhen both the muscles did not respond to a strong and weak stimuli. This is the condition of the fabric and is indicated as parabitamics.
Biological meaning of parabiasis
Parabitosis is not only a laboratory phenomenon, but a phenomenon that can develop in a holistic body under certain conditions. For example, a parabiotic phenomenon develops in the brain in a state of sleep. It should be noted that parabitosis as a physiological phenomenon is subject to the general-biodical law of force, with honors that the tissue response does not increase with the increased irritant, and decreases.
Medical meaning of parabiasis
Parabites underlies the action of local anesthetics. They reversibly bind to with specific areas located inside potential-dependent sodium channels. For the first time, a similar effect was seen in cocaine, however, due to toxicity and ability to cause a more secure analogues at the moment - lidocaine and tetrakain. One of the followers of the introduced, N.P. The jacks offered to consider the pathological process as parabios stage, therefore, anti-parabiotic means it is necessary to use it.
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Synonyms:Watch what is "parabitami" in other dictionaries:
Parabites ... Orphographic Dictionary
parabiosis - Functional changes in the nerve after the action of strong and long irritants described by N. E. Vvedensky. If the normal conditions are characterized by a direct and relatively proportional ratio of the force of the applied to the nerve ... ... Big psychological encyclopedia
Splicing, crossing the dictionary of Russian synonyms. Parabitosis of SUMS., Number of synonyms: 2 Crossing (27) ... Synonym dictionary
PARABIOSIS - (from Greek. Para near and BIOS Life), a term having a dual value. 1. Connection of two organisms in order to study mutual influences through blood and lymphatic systems. Parabezia experiments were carried out on mammals, birds and ... ... Big medical encyclopedia
- (from steam ... and Greek. BIOS Life) 1) The reaction of the live tissue to the effects of irritants (with a certain strength and duration of their action), accompanied by reversible changes in its basic properties of excitability and conductivity. Concept and theory ... ... Big Encyclopedic Dictionary
- (from Greek. Para nearby, near and BIOS Life) Functional changes in the nerve after action on it strong and long irritants described by N.E. Introduced. If normally is characterized by direct and relative ... Psychological Dictionary
- (from steam ... and ... biose), 1) the reaction of the excitable tissue on the effect of irritants, characterized in that the changed area of \u200b\u200bthe nerve (muscles) acquires low lability and therefore is not capable of carrying out a given rhythm of irritation. Concept and ... Biological Encyclopedic Dictionary
parabiosis - The method of obtaining parabiotic twins by connecting blood systems (anastomosis) or splicing their tissues. [Arefiev V.A., L. L. L. Anglo Russian Dictionary of Genetic Terms 1995 407s.] Themes of Genetics En Parabiosis ... Technical translator directory
PARABIOSIS - English.Parabiosis Ma.Parabiose Franz.Parabiose see\u003e ... Phytopathological Directory
- (cm. Couple ... + ... biose) 1) The method of artificial splicing of two animals, in which the general blood circulation is established between them; Apply. In biological experiments to study the mutual influence of organs and tissues of fragmented organisms ... ... Dictionary of foreign words of the Russian language
"His facts N. E. Vvedensky staged mainly
on nervous fiber. We found these facts in the central nervous system. "
NOT. Introduced released a book: "Excitation, braking and anesthesia", where showed that live tissue reacts to the external stimuli of items, its behavior represents several phases.
The first phase: "Provisional stage" by N.E. Introduced - this is the disappearance of differences in the action of weak and strong rhythmic irritations (in the domestic literature more often use the name of this phase given by his student - K.M. Bykov - "equalizing");
Second phase: "Paradoxical stage" by N.E. Introduced - a weak tissue reaction occurs on strong irritation, in response to weak irritations - a stronger response than strong irritation;
Third Stage: "Exaltation Stage" by N.E. Introduced - Loss of fabric ability to respond to irritation (in domestic literature, the name of this phase is usually used, given by K.M. Bykov - "brake").
I note that the works of N.E. The introduction was believed that the tissue reacts to externally irritation more or less equally. This is how the student N.N. writes about it. Introduced:
"The constancy of the reflex reaction was considered as the necessary starting point in the analyzes (and only there, since the arc works constantly, it was such a reliable element for analysis) that people trenderyly closed their eyes to the fact that the actual reflex arcs when we experimentally study and annoy them, can give extremely diverse effects, far beyond and sometimes even directly opposite to those that we expect to be squeezed. The doctrine of reflex perversions - "Reflex-Reversal", as English physiologists say. The topic of "Reflex-Reversal" is one of those that are extremely engabled to this day. Here - you feel - it is said that reflex arcs that we consider constricating devices, in some cases it is made as an exception and anomaly - give a deviation from the fact that they are relying in staff, deviations that reach even to the opposite. When we talk about "Reflex-Reversal", then you feel that some kind of norm is accepted, and this rate is taken for each reflex arc for a solid, the main phenomenon to which the anomalies and perversion are contacted. The school to which I belong, the school of professor N. E. Vvedensky, it does not look at the perversion of the effect on the same physiological substrate as something exclusive and anomalous. She considers them a common rule, for she is known, that constant reactions on the same substrate are obtained only depending on the defined conditions in which we observe this physiological apparatus - and we also know that when changing the conditions of irritation of the same substrate, as a rule, absolutely as the norm, we get the effect strongly rejected from the initial or even right to him the opposite , i.e. the excitation phenomenon goes into the phenomenon of braking. On the same substrate, depending on several independent variables: first, from the quantitative characteristic of the stimulus, it is from the frequency of the stimulus and from its strength, then, on the state of functional mobility, in which the reactive device is now, - we have effects , we naturally turn from excitement to braking. "
Ukhtomsky A.A., Dominanta, m., - l., "Science", 1966, p. 73-74.
And further:
"According to NOT. Introduced, braking is a kind of excitation modification: the propagating excitation is naturally converted into a non-prolonged, stagnant process, or a standing wave (braking). This pattern is that the higher the rhythm of the impact impulses and the lower labeliness of nervous formationsThe faster and easier excitement goes into braking. Thus, the opposite of these two processes is purely functional with the generality of the physico-chemical basis. "
Kondakov N.I., the history of philosophy in the USSR in five volumes, volume III, M., "Science", 1968, p. 484.
