| 释义 |
DictionarySeeadrenergicEncyclopediaSeereceptoradrenergic receptors
ad·re·ner·gic re·cep·torsreactive components of effector tissues, most of which are innervated by adrenergic postganglionic fibers of the sympathetic nervous system. Such receptors can be activated by norepinephrine and/or epinephrine and by various adrenergic drugs; receptor activation results in a change in effector tissue function, such as contraction of arteriolar muscles or relaxation of bronchial muscles; adrenergic receptors are divided into α-receptors and β-receptors, on the basis of their response to various adrenergic activating and blocking agents. Synonym(s): adrenoceptor, adrenoreceptorsad·re·ner·gic re·cep·tors (ad'rĕ-nĕr'jik rĕ-sep'tŏrz) Reactive components of effector tissues, most of which are innervated by the sympathetic nervous system. Such receptors can be activated by norepinephrine, epinephrine, and adrenergic drugs; receptor activation results in a change in effector tissue function, such as contraction of arteriolar muscles or relaxation of bronchial muscles.
Synonym(s): adrenoreceptor. adrenergic receptors Receptors which are stimulated by the catecholamines adrenaline (epinephrine) and noradrenaline (norepinephrine). These receptors belong to a family of G protein coupled receptors and are found in the central nervous system and many tissues innervated by the peripheral nervous system. There are two types of adrenergic receptors: (1) α-receptors, which are mainly excitatory to smooth muscles and gland cells but cause relaxation of intestinal smooth muscles; (2) β-receptors of which there are (at least) two types, β1 and β2. Generally, stimulation of β-receptors produces an inhibitory response, although in some cases the effect is excitatory (e.g. in the heart). Example: the dilator pupillae muscle contains mainly α-adrenergic receptors and stimulation (e.g. with adrenaline) produces mydriasis. On the other hand, there are drugs that block the effect of catecholamines on α- or β-adrenergic receptors and are called α- or β-blockers (or sympatholytic drugs or adrenergic receptor agonists). Example: the ciliary epithelium contains mainly β-receptors and a β-blocker such as timolol inhibits the secretion of aqueous humour, thus reducing intraocular pressure. Syn. adrenoceptor. See alpha-adrenergic agonists; alpha-adrenergic antagonists; beta-blocker; miotics; mydriatic; sympatholytic drugs; sympathomimetic drugs; autonomic nervous system.ad·re·ner·gic re·cep·tors (ad'rĕ-nĕr'jik rĕ-sep'tŏrz) Reactive components of effector tissues, most of which are innervated by adrenergic postganglionic fibers of the sympathetic nervous system. Such receptors can be activated by norepinephrine and/or epinephrine and by various adrenergic drugs.
Synonym(s): adrenoceptor. |