Beta Adrenergic Antagonist
A Beta Adrenergic Antagonist is an adrenergic antagonist that blocks beta receptors.
- AKA: β-Blocker.
- Context:
- It can Reduce Heart Rate, Reduce Blood Pressure, and other Sympathetic Nervous System activities.
- It can range from being a Selective Beta Blocker (targeting only one type of beta receptor) to being a Non-Selective Beta Blocker.
- ...
- Example(s):
- Selective Beta Blockers:
- Metoprolol (targets Beta-1 Adrenergic Receptors).
- Atenolol (also targets Beta-1 Adrenergic Receptors).
- Bisoprolol (primarily affects Beta-1 Adrenergic Receptors).
- ...
- Non-Selective Beta Blockers:
- Propranolol (affects both Beta-1 and Beta-2 Adrenergic Receptors).
- Timolol (also affects both Beta-1 and Beta-2 Adrenergic Receptors).
- Sotalol (acts on Beta-1 and Beta-2 Adrenergic Receptors, with additional antiarrhythmic properties).
- ...
- Selective Beta Blockers:
- See: Calcium Channel Blockers, Hypertension, Heart Arrhythmia, Beta Receptor, Competitive Antagonist, Catecholamine.
References
2023
- (Wikipedia, 2023) ⇒ https://en.wikipedia.org/wiki/beta_blocker Retrieved:2023-12-18.
- Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage abnormal heart rhythms (arrhythmia), and to protect the heart from a second heart attack after a first heart attack (secondary prevention). They are also widely used to treat high blood pressure, although they are no longer the first choice for initial treatment of most patients.
Beta blockers are competitive antagonists that block the receptor sites for the endogenous catecholamines epinephrine (adrenaline) and norepinephrine (noradrenaline) on adrenergic beta receptors, of the sympathetic nervous system, which mediates the fight-or-flight response. Some block activation of all types of β-adrenergic receptors and others are selective for one of the three known types of beta receptors, designated β1, β2 and β3 receptors.[1]β1-adrenergic receptors are located mainly in the heart and in the kidneys.[2] β2-adrenergic receptors are located mainly in the lungs, gastrointestinal tract, liver, uterus, vascular smooth muscle, and skeletal muscle.[2] β3-adrenergic receptors are located in fat cells.
Beta receptors are found on cells of the heart muscles, smooth muscles, airways, arteries, kidneys, and other tissues that are part of the sympathetic nervous system and lead to stress responses, especially when they are stimulated by epinephrine (adrenaline). Beta blockers interfere with the binding to the receptor of epinephrine and other stress hormones and weaken the effects of stress hormones.
In 1964, James Black synthesized the first clinically significant beta blockers—propranolol and pronethalol; it revolutionized the medical management of angina pectoris and is considered by many to be one of the most important contributions to clinical medicine and pharmacology of the 20th century.
For the treatment of primary hypertension, meta-analyses of studies which mostly used atenolol have shown that although beta blockers are more effective than placebo in preventing stroke and total cardiovascular events, they are not as effective as diuretics, medications inhibiting the renin–angiotensin system (e.g., ACE inhibitors), or calcium channel blockers.
- Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage abnormal heart rhythms (arrhythmia), and to protect the heart from a second heart attack after a first heart attack (secondary prevention). They are also widely used to treat high blood pressure, although they are no longer the first choice for initial treatment of most patients.