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Neurogenic regulation of respiratory tracts.

the Reason of change of a bronchial tonus considers balance disturbance between raising (cholinergic, not cholinergic and alpha adrenergic system) and inhibiting (beta adrenergic and not adrenergic inhibiting systems) [Bames, 1992].

Among transmitters in system of the nervous control over a tonus of a bronchial tree the important place is occupied with neuropeptids: substance R and vasoactive intestinalnyj a peptide. Substance R - nejrotransmitter not cholinergic exciting nerves is surveyed now as the basic mediator of the neurogenic inflammation, capable to cause such pathophysiological reactions, as an edema, a slime hypersecretion, a bronchospasm. It is necessary to underline, that the neurogenic inflammation with participation of neuropeptids can accompany and aggravate already available allergic inflammation which initiator is reagin-dependent reaction. There are facts of an interconnection of an allergic and neurogenic inflammation. The sensitive nervous terminations, in particular the terminations nemiepinizirovannyh the S-fibers, carrying substance R, nejrokinin And and other neuropeptids bound to them, can be activated under the influence of inflammation mediators (a bradikinin, Histaminum, VEILS, lejkotrienov), including in a pathogenesis of an asthma the mechanism of an axon-reflex and framing thus a vicious circle, strengthening and extending an initial inflammation. Many nonspecific stimulus (for example, a smoke, sulphur dioxide) provoke a reflex bronchospasm with participation of the sensory terminations liberating substance of R.Pokazano, that at is long remaining inflammatory process there is a proliferation of nervous fibers. Carrying substance R with augmentation of liberation of a neuropeptid. The effects of a neurogenic inflammation shown in the course of disease, influence its gravity and a current.

the Core nejrotransmitterom not adrenergic - not cholinergic system is vasoactive intestinalnyj a peptide. It is known, that vazointestinalnyj the peptide is the important regulator of a bronchial tonus, to the most powerful endogenous bronhodiljatatorom from known now and is capable to counteract a bronchospasm at an asthma. It is probable, that dysfunction in the VIP to system can again arise in the course of an inflammation of respiratory tracts at an asthma. Formation of hypersensitivity of respiratory tracts and a reflex bronchospasm can be bound to the strengthened degradation of this neuropeptid at sick of a bronchial asthma. The VIP, as well as in 2 -agonists, raises level tsamf in a respiratory epithelium. Occurrence of the given neuropeptid in regulation system is a bright example of functional unity of neuroendocrinal regulation at BA.

It is necessary to notice also, that in realisation of effects of neuropeptids the great value has activity of a neutral endopeptidase - enzima, being on a surface, containing receptors for neuropeptids, epithelial cells of bronchuses, gladkomyshechnyh cells, endothelial cells. A neutral endopeptidase

splits and inactivates neuropeptids, limiting thus their concentration on receptors of a cellular surface, and is modulated by the answer of cells-targets. Change of activity of a neutral endopeptidase also can matter at exacerbation BA.

the Basic researches in genesis BA concerned in 2 -adrenoreceptors in a smooth musculation.

Defect adrenoretseptsii, inherent in patients with a bronchial asthma. Is a constitutional sign, characteristic for atopy A.Szentivanyi. Radio graphic them kartirovanie shows, that they concern to in 2 to a-subtype and are present at all levels of a respiratory tract. In epitheliocytes level of m - RNK in 2 -adrenoreceptors is high, that is intensity of a transcription is high, in 2 - adrenoagonisty raise transport of ions through an epithelium, frequency of palpation of cilia and, accordingly, mukotsiliarnyj a clearance. agonists Influence secretion of mediators and cytokines - is not clear. This question rather we mean, for inhalated agonists in 2 -adrenoreceptors are capable to reach a respiratory epithelium in high concentration. Up to the end communication in 2 - adrenoreceptors with ionic channels is not defined, regulation of receptor structures [Terran L.M is not taped., Davies D.E., 1996]. On the other hand, steroids raise an expression in 2 - adrenoreceptors at the expense of intensifying of a gene transcription. Therapy by small doses
steroids can prevent a dysregulation agonists in 2 the-adrenoreceptors, come as a result of constant application of agonists in 2 -adrenoreceptors.

It is known, that a-adrenoretseptory by the nature share on two subtypes: аі and and 2 . a_-adrenoretseptory are localised in postsinapticheskih membranes (in vessels and a smooth musculation of distal bronchuses, it is probable them and is caused weak a-stimulirovannaja bronhokonstriktsija). A2-receptors are located vnesinapticheski in a wall of vessels (within the limits of this discussion are not surveyed pre - and postsinapticheskie a2-receptors in TSNS). Antiedematous action of a-stimulators is realised, first, immediate a1-postsinapticheskim by action in microvessels mucous bronchuses, secondly, immediate a2-vnesinapticheskim action in vessels, and also a2 - the stimulation leading to liberation of Noradrenalinum, having mainly a1-stimulating an effect. In a case with a bronchial tree and - adrenostimuljatsija leads to mainly antiedematous effect as a result of narrowing of vessels of a mucosa of bronchuses.

As the basic mechanism of antiedematous action of adrenaline is narrowing of vessels of a microcirculatory bed and reduction of their permeability it is possible to assert confidently, that expressed bronhokonstriktornaja reaction after adrenaline inhalation develops owing to stimulation of a-adrenoreceptors of vessels mucous and decreases of its edema with the subsequent moving of mucous stoppers from peripheric bronchuses, instead of stimulation of a-receptors of a smooth musculation. If occurrence a-stimulirovannoj bronhokonstriktsii has been caused by stimulation and - receptors of a bronchial musculation, appointment of expectorating therapy under various schemes (peroral or inhalation) would not render essential influence on this reaction. The given explanation of the mechanism of development a-stimulirovannoj bronhokonstriktsii will well be compounded, first, with the assumption of a constancy of antiedematous effect of adrenaline, secondly, with for a long time existing opinion that in obstruction of peripheric bronchuses the prevailing mechanism is not the spastic stricture, and an edema mucous with an obturation their mucous stoppers, and, thirdly, with cases of an aggravation of symptoms of patients available in clinical practice after introduction of adrenaline by it [Parsons G. H, 1984].

As to weak and-stimulirovannoj bronhokonstriktsii, as it is reversible cholinolytics, it is necessary to consider it reflex. This reaction owing to the reflex mechanism of occurrence can be caused not only mechanical (movement
mucous stoppers), but also physical (osmotic) or chemical (change pH) influence of inhalated a-stimulators on mucous bronchuses that proves to be true also literature data [Snashall P.D., Boother F.A., Sterling G.M., 1978] though they in a sufficient measure are inconsistent.

the Detailed analysis of degree of expression and time of occurrence the alpha - stimulirovannoj bronhokonstriktsii depending on specific features of the patient, also taps curious patterns.

Dependence of size a-stimulirovannoj bronhokonstriktsii from a floor of subjects is shown by that at women it authentically above in spite of the fact that average duration of disease at them is less. Thus the parity of women and men with bronhokonstriktsiej on adrenaline makes 3:1, that exceeds this indicator in all surveyed population - 2,35:1. Possibly, it speaks opposite influence of female and man's sexual hormones on asthma evolution: estrogens render negative, and androgens - positive action. It proves to be true also presence of direct correlation dependence between degree bronhokonstriktsii and age of men as in the course of ageing, as is known, activity of androgens decreases. Apparently, frequent cases of deterioration of a current of an asthma against dishormonal changes at women, in particular at pregnancy [Henson F.V., 1984], are bound to frequency augmentation bronhokonstriktornyh reactions. Most possibly, what exactly various specificity of action of man's and female sexual hormones causes higher case rate of women during the age period from 10 till 60 years [Fife D, Spejzer F.E., 1984]. Steroids, take out an edema and an inflammation, slow down advance BA and are basic preparations in treatment BA [Heide D., 1984].

a Fig. 23. Evolution of bronchial obstruction at sick of an asthma

That fact, that evolution of bronchial obstruction (fig. 23) at an asthma is bound first of all with change of the answer to adrenaline, has the important biological value. Endogenous catecholamins (adrenaline or Noradrenalinum), being natural adrenergic regulators of function of lungs, in a disease initial stage render bronhorasshirjajushchee and antiedematous action. Endogenous catecholamins, circulating in blood, have constant influence on pathophysiological mechanisms of an asthma. And from that, their production is how much high and constant, the further current and the disease forecast in many respects depends. As to exogenously arriving in an organism selective simpatomimetikov, in particular, beroteka, Ventolinum and so forth their high selectivity and incidental character of application do not allow to influence all pathophysiological mechanisms of an asthma and by that to interfere with advance of bronchial obstruction. The pharmacological testing spent only with selective in 2 -

simpatomimetikami does not allow to tap in population of patients identical at first sight all features of formation and evolution of bronchial obstruction.


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Scientific source INGA MAMUCHISHVILI. INTERRELATION STRESS-INDUCED of DISTURBANCES In nejrogumoralnoj to SYSTEM And SYSTEM of POWER SUPPLY At TEENAGERS. The DISSERTATION on competition of a scientific degree of the doctor of medical sciences. Tbilisi - 2006. 2006

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Other medical related information Neurogenic regulation of respiratory tracts.:

  1. THE MAINTENANCE
  2. Neurogenic regulation of respiratory tracts.
  3. THE LITERATURE LIST
  4. Clinico-Anamnestichesky and urodinamicheskie research methods.
  5. ZAKLJUCHEIIE.