adrenergic receptor

biology

Also known as: adrenoceptor

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July 23, 2026

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Adrenergic receptors, also known as adrenoceptors, are proteins found on the surface of cells that bind to catecholamines like epinephrine and norepinephrine. These receptors are crucial components of the sympathetic nervous system, which is responsible for the body's "fight-or-flight response".1234

There are two main types of adrenergic receptors: alpha (\u03b1) and beta (\u03b2), each with further subtypes (\u03b1₁, \u03b1₂, \u03b2₁, \u03b2₂, \u03b2₃). When stimulated by catecholamines, these receptors trigger various physiological changes. For instance, alpha receptors primarily cause blood vessel constriction, increasing blood pressure, while beta receptors can increase heart rate and contractility, and relax smooth muscles in the airways.15324

Drugs that mimic or block the action of these receptors are known as adrenergic drugs and are used to treat conditions such as asthma, shock, and high blood pressure.36

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…is said to be an adrenoceptor. Ahlquist called the two kinds of adrenoceptor alpha (α) and beta (β). This theory was confirmed when Sir James Black developed a new type of drug that was selective for the β-adrenoceptor.
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…is said to be an adrenoceptor. Ahlquist called the two kinds of adrenoceptor alpha (α) and beta (β). This theory was confirmed when Sir James Black developed a new type of drug that was selective for the β-adrenoceptor.
Read More