Adrenolytics or antiadrenergic means lower tone of the sympathetic division of the autonomic nervous system. Considering the mechanism of action, they are divided into blockers (non-selective and selective - depending on the selectivity of action on the adrenergic receptor types and subtypes) and sympatholytics. Blockers shield (close) adrenergic receptors and interfere with the interaction with them norepinephrine, respectively, causing effects opposite to those that develop due to exposure adrenomimeticheskih funds. Blockade of postsynaptic vascular alpha1 receptor contributes to their expansion, cardiac beta1-receptors - the weakening and slowing of heart rate, decrease automaticity and slow AV conduction, beta2 receptor - a narrowing of the small blood vessels and raise bronchial tone.
Alpha-blockers are mostly prescribed for hypertensive conditions and diseases associated with narrowing of peripheral vessels; Beta-blockers used as an antiarrhythmic, antianginal and antihypertensive agents.