β-adrenoblockers

β-adrenoblockers were framed (and are now used) as remedies for coronary heart disease (stenocardia, a myocardial infarction), tachyarrhythmias, complex treatment of hypertensia. Restrictions for use of these drugs in sport began in 1984. For today, if other isn't specified, β-adrenoblockers are forbidden only at competitions in the following sports:

• aeronautics (FAI);
• archery (FITA, IPC) (are also forbidden out of competitions);
• motoring (FIA);
• billiard sport (WCBS);
• bobsled (FIBT);
• water motor sport (UIM);
• bowling (CMSB, IPC);
• bridge (FMB);
• curling (WCF);
• gymnastics (FIG);
• motorcycle sport (FIM);
• modern pentathlon (UIPM) — for the disciplines including firing;
• bowling of the nine-pin (FIQ) version;
• sailing (ISAF) (only in match races);
• firing (ISSF, IPC) (are forbidden constantly!);
• ski sport / snowboarding (FIS) (ski jumping, freestyle, snowboard);
• fight (FILA).

To WADA classification, treat β-adrenoblokator (the list isn't exhaustive): alprenolol, atenolol, atsebutolol, betacsolol, bisoprolol, bunolol, carvediol, carteolol, labetalol, levobunolol, metypranolol, metoprolol, mildronate, nadolol, ocsprenolol, pindolol, propanolol, sotalol, timolol, tseliprolol, esmolol.

Considering pharmacology of β-adrenoblokator, it is necessary to stop shortly on all group of means — the medicines blocking transfer of excitement. Two main groups of medicines treat them: adrenoblokator (block adrenoceptors) and sympatholytics (break synthesis, deposition and allocation of catecholamines).

Adrenoblokatorami are called the means blocking adrenoceptors. They interfere with action of noradrenaline. According to different types of adrenoceptors they are divided on and-adrenoblokatory (prazozin, pirroksan, doksa-zozin (kardura)) also by β-adrenoblokator (anaprilin, atenolol, metoprolol, tapinolol, etc.), and also on and - β-adrenoblokator (carvedilol, labetalol). Apparently from the given classification, carvedilol and labetalol, the carried WADA to β-adrenoblokator, actually are and-β- adrenoblokators.

a-Adrenoblokatory divide into the means blocking and, and a2 adrenoceptors, and the means blocking only and, - adrenoceptors. Carry phentolamine to not selective (regitin), pirroksan (pro-rock dignity), nitsergolin (cavinton), oksibrat (vinkamin), the dihydrogenated ergot alkaloids (dihydroergotamine, digidroergotoksin, digidroergokristin).

Phentolamin (Regitinum) in Ukraine isn't registered. This derivative imidazoline is characterized short-term and - adrenoceptor blocking, vasodilating, hypotensive by actions. Causes tachycardia, increases motility of a GIT, enlarges secretion of glands of a stomach, slightly stimulates β-cells of islets of Langerhans.

Indications to use: spastic stricture of peripheric vessels (Rae's illness but also other), diagnostics and treatment of a pheochromocytoma.

Side effects: tachycardia, giddiness, hyperemia and itch of a skin, nose mucosa swelling, nausea, vomiting, orthostatic collapse.

Pyrroxan — and - adrenoblocker of the central action, generally blocks and - adrenoreceptors in structures of a brain (for example, in a core of a back hypothalamus), regulates activity of simpatikoadrenalovy system. Drug has sedative properties, eliminates hyperemia symptoms, lowers arterial pressure at various diseases bound to rising of excitability of diencephalic structures increases working capacity, eliminates a headache, tension, feeling of alarm, a dermal itch, vestibular symptoms.

Indications to use: arterial hypertension, dientsefalichny crisis, pruritic dermatoses, aeroembolism, morphinic abstinence.

Side effects: hypotension, bradycardia, intensifying of pains in heart.

Side effects are noted at drug of a butiroksan.

Digitirovanny alkaloids of an ergot (dihydroergotaminum, a dihydroergotoxin, äèãèäðîýðãîêðèñòèí) dilate vessels and lower arterial pressure, possess sedation, veno-tonic action. Are a part of whole I am glad the combined antihypertensives (adelzin, kristepen, brinerdin, cormazen, etc.).

To selective and, - to adrenoblockers carry anti-hypertensive drugs Prazozinum (Minipressum), doksazonin (cardura), terazozin (korna).

Prazozin blocks postsynaptic and, - adrenoreceptors and possesses myotropic spasmolytic action as a result of phosphodiesterase blockade. Besides, blocking α-adrenoreceptors, reduces a tonus of muscles of a neck of a bladder, a prostate, a prostatic part of an urethra that leads to augmentation of rate of outflow of urine in general and to outflow augmentation from a bladder.

Drug can cause a lowering of arterial pressure, decrease of venous inflow to heart, final diastolic pressure in heart ventricles, decrease of pressure in the pool of a pulmonary artery, simplification of work of heart, inhibition of glycogenolysis and improvement of a lipide range of a blood plasma. Duration of effect is 6 — 8 h.

Doksazozin (cardura) and Terozinin are close (korna) on structure and action to Prazozinum. Are a selective blocker postsynaptic and, - adrenoreceptors. In comparison with Prazozinum have the prolonged effect to 24 h.

Alfuzozin (dalfaz), tamsulozin (omnik), selective and, - adrenoblockers.

Indications to use: good-quality hyperplasia of a prostate, hypertensia.

Side effects: tachycardia, a headache, giddiness, a nose congestion (a mucosa swelling owing to vasodilatation), an orthostatic collapse, disturbance of a cordial rhythm, the dispepsichesky phenomena, an acceleration of an emiction, fatigability.

β-adrenoblockers - - - - - - - - - - agents which selectively block β-adrenoreceptors of heart, vessels, bronchi and other organs. Drugs which selectively block β1-àäðåíîðåöåïòîðû call cardioselective.

β-adrenoblockers differ not only ability to block β1-and β2-àäðåíîðåöåïòîðû, but also existence of internal sympathomimetic activity and membrane stabilizing activity. Classification of these drugs is based on their ability to block various subtypes of p-adrenoreceptors.

1. Not selective β1-, β2- adrenoblockers.

1.1. Without internal sympathomimetic activity — Propranololum (anaprilin), Nadololum (Corgardum), Timololum (oftan Timololum). 1.2. With sympathomimetic activity — Pindololum (Viskenum).

2. Selective β1- alrenoblockers..

2.1. Without internal sympathomimetic activity — metoprolol (Corvitolum), atenolol (atenobeks), betaksolol (locren), bisoprolol (konkor), nemeolol (not ticket).

2.2. With sympathomimetic activity — tseliprolol (tseliprol), Talinololum (cordanum), atsebutolol (sektral), espanolol (breviblok).

3. alpha, beta Adrenoblockers — carveolilol (coriol), labetolol (lakardit).

Possess membrane stabilizing action (decrease of permeability of membranes for ions of sodium and a potassium) Propranololum, atsebutolol, Nadololum, Pindololum is less.

Pharmakodinamika of β-adrenoblokator is characterized by three types of action — antianginalny, antiarrhytmic and hypotensive.

1. Antianginalny action is connected with leveling of positive inotropny and hronotropny effects of catecholamines (decrease in force and heart rate) that leads to reduction of need of a cardiac muscle for oxygen. Besides, these medicines block metabolic effects of catecholamines (strengthening of processes of a glikogenoliz, lipoliz — the main exchange). It, in turn, promotes antianginalny action as decrease in energy costs of a myocardium and redistribution of coronary blood circulation happen for benefit of the ischemic centers.

2. Antiarrhytmic action is connected with decrease in excitability and automatism in a sinus node of the carrying-out system of heart, conductivity delay as medicines block β-receptors of a sinus node.

3. The hypotensive effect is connected with reduction of warm emission and activity of reninangiotenzinovy system. Resistance of peripheral vessels under the influence of p-adrenoblokatorov can increase reflex because of reduction of warm emission.

β-Adrenoblokatora influence not only cardiovascular system, but also other bodies, in different degree. So, medicines can break concentration of attention when driving the car, having the oppressing effect on TsNS, to exert the stimulating impact on a uterus and bronchial tubes.

Anaprilin (Propranololum, Obsidanum) blocks both β1-, and β2-adrenoreceptors. Blocking β1-adrenoreceptors, anaprilin weakens and reductions of heart, reduces oxygen consumption, reduces automatism of heart, reduces cordial emission. At systematic use drug reduces arterial pressure. The tonus of blood vessels anaprilin raises in the beginning (blockade β2- adrenoreceptors) therefore in the first days of use of drug arterial pressure can not change. But at further use of anaprilin blood vessels extend (reaction of vessels to long depression of cordial emission) and arterial pressure decreases. Anaprilin reduces allocation of renin kidneys (blockade P, - adrenoreceptors) that matters for realization of hypotensive effect. Anaprilin raises a tonus of bronchi and an intestine. Drug reduces activity of a lipolysis, insulin secretion, tolerance to glucose.

Talinolol (cordanum) doesn't cause a bronchospasm, and for the rest effects are similar to those of atenolol. It is carefully necessary to prescribe to pregnant women (use of an injection form of drug is undesirable because of a possibility of action of a dissolvent — propylene glycol).

Bisoprolol possesses mainly anti-anginal, hypotensive action, eliminates the phenomena of a heart failure.

Indications to use: stable stenocardia (rest, a strain), arrhythmias (especially sinus tachycardia), an idiopathic hypertensia (in an initial stage).

Metoprolol (the prolonged form), áèñîïðîëîë, êàðâåäèëîë apply at a chronic heart failure.

and-β-adreblocator carvedilol (coriol) has also antioxidatic properties, hypotensive effect, reduces the phenomena of a heart failure, a hypertrophy of a left ventricle, influences lipide range doesn't change glucose level in a blood less.

β-adrenoblockers rather seldom cause complications or side effects, such as hypotension, a bradycardia, an asystolia, a congestive heart failure, disturbances in a GIT and digestion, constipations, nausea, dryness in a mouth, tension of muscles, bronchospasm, an impotency, psychological disturbances, toxic psychoses, a hallucination, euphoria, disturbances of concentration of attention, an ataxic gate, a headache, giddiness, delicacy, a flaccidity, a sleepiness. In rare instances reception of these drugs causes an agranulocytosis, thrombocytopenic and I will hold down purpura, an eruption, dermal reactions.

Atenolol — cardioselective hydrophylic β1-àäðåíîáëîêàòîð, has anti-anginal, hypotensive and antiarrhytmic effects. Reduces excitability of a myocardium. Exerts less expressed impact on a smooth musculation of bronchi and peripheric arteries, than not selective r-adrenoblockers.

Metoprolol is cardioselective β1-àäðåíîáëîêàòîðîì though on selectivity of action concedes to an atenolol a little, can reduce the phenomena of a heart failure in the prolonged form. Exerts insignificant impact on β2-àäðåíîðåöåïòîðû bronchi and vessels, gets through a hematoencephalic barrier.

Adrenoblockers should be distinguished from sympatholytics (sympatholytics). Drugs from group of simpatiolitik block a sympathetic innervation at the level of the terminations of postganglionic (adrenergic) fibers. Unlike adrenoblockers, they don't influence adrenoreceptors and don't reduce action the adre-nomimeticheskikh of agents, and even on the contrary, strengthen their action. Different sympatholytics can have various mechanisms of blockade of the terminations of adrenergic nervous fibers, however the end result of action of these agents is identical: they reduce allocation of a mediator the adrenergic nervous terminations. Sympatholytics eliminate the stimulating influence of a sympathetic innervation on heart and blood vessels — there is bradycardia, force of cordial reductions decreases, blood vessels extend and arterial pressure decreases.

Reserpin — an alkaloid of Rauwolfia serpentine (Rauwolfia serpentaria Benth.), growing in India. Reserpinum has ability to collect in a membrane of vesicles in the terminations of adrenergic fibers. Drug promotes destruction of the ATP complex with Noradrenalinum and itself forms complexes with ATP.

Reserpin breaks process of deposition of Noradrenalinum in vesicles, the return capture of catecholamins oppresses, and also breaks their synthesis. As a result the maintenance of Noradrenalinum in the terminations of adrenergic fibers decreases owing to what transfer of exaltation in adrenergic synapses is broken.

Reserpin easily gets through a barrier and reduces the maintenance of Noradrenalinum in a CNS. Its sedative and antipsychotic action is bound to it. Therefore Reserpinum is carried also to group of antipsychotic (antipsychotic) agents. Drug promotes development of a dream. Strengthens effect of hypnotic drugs and anesthetics. A little respiration oppresses, reduces body temperature.

Hypotensive effect of Reserpinum is caused by its peripheric (sympatholytic) action. Arterial pressure at introduction of Reserpinum decreases gradually (the maximum effect is observed in several days). Hypotension at long introduction of Reserpinum is bound to decrease of the general peripheric resistance of vessels and oppression of pressor reflexes. Oppression by Reserpinum of an adrenergic innervation - results in prevalence of cholinergic effects. It is shown by a bradycardia, rising of a secretory and physical activity of a GIT, miosis.

Indications to use: arterial hypertension.

Side effects: giddiness, sleepiness, hyperemia of the person, narrowing of pupils, bradycardia, arrhythmias, hypotension, dermal eruption, dyspeptic phenomena, depression of sexual activity.

Raunatin contains the sum of alkaloids from Rauwolfia roots.

Pharmacological properties of Raunatinum are bound to existence in it of Reserpinum.

Indications to use: arterial hypertension.

Side effects: are less expressed in comparison with Reserpinum.

Methyldopa (Aldometum, dopegit) gets through a hematoencephalic barrier into a CNS where as a result of decarboxylation turns in and - methylnoradrenalinum (a false mediator). The last is an active stimulator central and - adrenoreceptors. Methyldopa breaks also a biosynthesis of catecholamins, reduces concentration of Noradrenalinum, forces out it from the nervous terminations. Besides, the false mediator itself is bound with and, - adrenoreceptors of unstriated muscles of a vascular wall that reduces pressor effect of Noradrenalinum. As a result of this competition vasoconstrictive action decreases and arterial pressure decreases. The hypotensive effect occurs in 4 — 6 h and 2 days last.

Methyldopa rhythm of cordial reductions, improves a renal blood stream, strengthens diuresis, causes sedation, exponentiates effect of hypnotic drugs and neuroleptics. Indications to use: arterial hypertension.

Side effects: a sleepiness, an orthostatic collapse, a depression, a nose congestion, dryness in a mouth, rising of a motility of a GIT (spastic strictures of a stomach and an intestine, diarrhea), a delay of ions of sodium and water, dermal rashes, agranulocytosis, thrombocytopenia, an impotency.

Octadin — a sympatholytic of peripheric action, replaces Noradrenalinum in the intraneyronalnykh vesicles, Noradrenalinum is allocated from vesicles, its return capture is blocked, Noradrenalinum is inactivated a catechol-au-methyltransferase, partially a monoaminooxidase.

Drug gradually reduces the arterial pressure, the general peripheric resistance of vessels. In high doses perhaps curariform action, slightly lowers intraocular pressure.

Indications to use: arterial hypertension.

Side effects: an orthostatic collapse, short rising of arterial pressure, peripheric edemas, dryness in a mouth, pain in a thorax, a dyspnea, a bradycardia, a diarrhea, a nose congestion, the general delicacy, giddiness, nausea or vomiting.

Features of use of β-adrenoblockers in practice of sports preparation

β-Adrenoblokatora gained distribution in sport as the medicines suppressing activity of the central nervous system and other physiological systems. Their application promotes reduction of frequency and lowering of force of warm abbreviations, reduction of minute volume of blood (warm burst), and, as a result — to lowering of need of a myocardium for oxygen. At the same time excitability and conductivity of a myocardium decrease.

In sport β-adrenoblokator are used for suppression of excessive excitation, lowering of a tremor, frequency of abbreviations of heart that can be effective in the course of competitive activities in such sports as firing from the gun, archery. Can be the useful and for jumpers on skis from a springboard, bobsledders, lugers. Separate of substances of this class can be also used for a distance of approach of guarding braking, overcoming pain.

At the same time p-adrenoblokatory exert the negative impact on effectiveness in the sports connected to endurance manifestation and also the types requiring high coordination, bystry response, etc. For example, application of p-adrenoblokatorov oppresses function of cardiovascular system, reduces the content of hemoglobin and the free fatty acids in blood.