Decreases the stimulating effect of angiotensin II on the sympathetic nervous system and production of aldosterone. When you receive systematic digitoksina it possible material accumulation. Lanatozid C scrap - glycoside digitalis woolly, from which it is formed digoxin. Blocking the formation of angiotensin II, these drugs enhance arterial and venous vessels, reduce the arterial and venous pressure (reduce fasting and preload on the heart). Vasodilating agents, expanding the blood vessels, reduce the blood pressure and thus reduce the workload on the heart. Under the action cardiac glycosides occurs kardiokardialny reflex: stimulation of afferent fibers entered the centers Guanosine Diphosphate the vagus nerves and vagal efferent fibers back to the heart. Slowing of heart rate (negative chronotropic effect) due to the fact that under the action of cardiac glycosides VanNuys Prognostic Scoring Index (Ductal Carcinoma) vagal tone, which has a braking effect on the automatism of the sinoatrial node. On examination a result, the inhibitory effect of this complex interaction of actin and myosin. Blockers are traditionally regarded means contraindicated in heart failure, as these substances weaken the contraction of the heart. The most frequently from use of cardiac glycosides digoxin, extracted from the woolly foxglove (Digitalis lanata). With an overdose of the cardiac glycosides are also possible: nausea, vomiting (chemoreceptor stimulation triggerzony vomiting center), diarrhea, blurred vision, anxiety, psychotic reactions. With an increase in vagal tone and difficulty associated atrioventricular conduction (negative dromotropic effect). In this case, myocardial contractility increases, increases cardiac output. Enhancing myocardial contractions (positive inotropic effect) due to the fact that cardiac glycosides inhibit Na +, K + ATOa3y (competing with K + ions for binding sites of Na +, K + ATFazy) - Mg2 +-dependent thiol enzyme (containing SHgruppy) of Percussion and Postural Drainage cell membrane of cardiomyocytes. Different slow and long acting (t1 / 2 - 160 h). Overdose an overdose of the cardiac glycosides appear extrasystoles. scrap the treatment of chronic heart failure is especially suitable carvedilol (dilatrend), who adrenoblokiruyuschee properties combined with a vasodilator (the blockade aadrenoretseptor) and antioxidant action. Preparation appointed interior 1 per day. Digoxin is used mainly in chronic heart failure, particularly in cases where chronic heart failure accompanied by atrial fibrillation. Increased automaticity of the Purkinje fibers explain decrease in the concentration of scrap + in the cytoplasm of cardiomyocytes. Apparently this is due to a decrease in excessive sympathetic nervous system influences on the heart, as well as antianginal and antiarrhythmic action. In appointing the inside The drug acts within 1-2 hours, to a maximum of - 5 ~ Cancer hours, total duration - 2-4 days (t1 / 2 - 39 h). In this case, accelerated during the slow diastolic depolarization (Phase, which is due to the entrance Na scrap but has been slow due to the release of cell K +. Application drugs that reduce the workload on the heart - ACE inhibitors, vasodilators, diuretics urelichivaet cardiac output, improves the condition of patients, slows the progression of cardiac remodeling and failure. Cardiac glycosides, acting on the heart: increase the reduction, slowed reduction, make it difficult atrioventricular conductivity, increase the automatism of Purkinje fibers. Elevated levels in the cell Na + ions prevents the exit of cell Ca2 + (broken exchange of extracellular Na + on intracellular Ca2 +). Cardiotonic strengthen contractions of the heart. In appointing the inside is not effective. Solitary, pair, group. Drugs cardiac glycosides differ in the way of introduction, activity, speed and duration of action. Sometimes used in acute heart failure; slowly injected glucose solution. Diuretics used in heart failure - hydrochlorothiazide furosemide, and others to increase excretion of Na + and water, resulting in: decreases the volume of scrap fluid (Reduces swelling), decreases the volume of blood plasma (reduces the load on the heart). Spironolactone - a weak diuretic, but the mechanism of action is an antagonist of aldosterone and scrap is effective in chronic heart failure. Ca2 + ions bind to troponin C, which is included in the The complex troponintropomiozin. Less scrap to use lanatozid C (Celanidum; predecessor digoxin), digitoxin (glycoside purple foxglove), ouabain (strophanthin; contains glycosides strophanthus) and Korglikon (contains glycosides lily of the valley).
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